just to add on a few point from what etigge saying,

1. handlepost
the verge x10/20 used tbar physis 3d handlepost height around 35cm while the P siries use qr handlepost height 39cm. u can bought the handlepost around rm450

2. syntace vro stem
the verge x10/20 used this stem, while P siries use non.u can buy this stem around rm180

3. syntace lighten seatpost and handlebar, kore saddle, ergon grip and others
well, this one u can customize urself. still have option worth like litepro or gub component that will not burn ur pocket

other than that, if u are crazy enough to build the color like x siries (repaint) the total cost will not over than buying x20 itself.

i calculated myself when converting my p9 wannabe x20. still cheaper and better component!

i heard before the x20 got cheaper as rm8.5k (my friend buy before), but that one in a million opportunity!

just to add on a few point from what etigge saying,

1. handlepost
the verge x10/20 used tbar physis 3d handlepost height around 35cm while the P siries use qr handlepost height 39cm. u can bought the handlepost around rm450

2. syntace vro stem
the verge x10/20 used this stem, while P siries use non.u can buy this stem around rm180

3. syntace lighten seatpost and handlebar, kore saddle, ergon grip and others
well, this one u can customize urself. still have option worth like litepro or gub component that will not burn ur pocket

other than that, if u are crazy enough to build the color like x siries (repaint) the total cost will not over than buying x20 itself.

i calculated myself when converting my p9 wannabe x20. still cheaper and better component!

i heard before the x20 got cheaper as rm8.5k (my friend buy before), but that one in a million opportunity!

And even cheaper option    The Crius frame which is the Dahon Vector which is also similar to the Tern Verge.  Slap everything Lite pro on it with Tiagra 2017 groupset. 

https://world.taobao.com/item/41909909750.h...0.6HV85s#detail

but hows the built quality ? tis brand is quite popular in thailand n the philipine wo...

I never said you can't use the Altus to operate a 10 speed RD. It can be use. The length of each gear pull or indexing is determine by the shifter. So, the RD just corresponds to the distance or length pulled or released. The limiters are there to limit the travel of the cage so the chains won't go over the limits, else it will fall out of the cogs. The total gap of the 8, 9 and 10 speed are the same. It is just the thickness of the cogs and distance apart from each cogs. Hence, the same hubs can either house 8, 9 or 10 speed cassettes. As for 11 speed, they are different and now 12 speed is coming out as the trend is now going for single chainring setups with smaller chainring and larger cassettes, so far up to 50 teeth now for the largest rear cogs.

The pull ratio is the same only that road bike shifters has something we call 'quarter shift' which shifts a little bit of the FD position to avoid chain rub on the FD. Nothing to do with the back setup. Go ahead and try it out. Never try never know, right? If you have to be so certain of everything before you try out, you won't go anywhere! 

PS/I do know is that SRAMs shifters need SRAMs RDs and are not interchangeble between the 2 brands. Ironically, Microshift shifters can be use on both systems. The pull ratio of the 2 main systems are different. But for FD operations, both are interchangeable, only the rear operations differs.

Etigge,
To update you after the change.

Went to LBS and the owner is kind enuff to help swapping of components to trouble shoot.
We tested with shimano 105 SS Rd, Sram Hollow pin 9 speed chain, and swapping Aerozine Alluminium 11t pulley from the get go....on existing 8spd SL-M310 shifter, and 8 speed 11-32Mtb cassette..and 52T single chainring
It seems to gel and work well...shifting works better than previous and definitely a different solid feel to the pedalling..likely the better chains effect.

So, in short...the mismatch components above somehow works nicely...tho not perfect...so, for rm350 damage..seems a pretty good upgrade deal.

Thx to etigge , azum and desastar for ur inputs.

Lately Thailand started selling clone Brompton, LA Neo Stage 201

Good to hear that ! 

You know those rear cage pulley, It kinds of boggles me. Some costs as much as 200 bucks for each and they are fitted with ceramic bearings. They blowed it hard and the pulley turns and turns and stops only after some time. What boggles me is this..................How does it help? I mean the pulley is cogged onto the chains, think for a second, when the chain stops, it also stops. So, we don't really need that inertia to help.  As long as it is not stuck, it's OK, right? If you say, hub bearings , Yes, that I can accept and maybe bottom bracket bearings but pulley bearings, hmmmmm............

Yeah etigge, not sure if it has any impact, other than looks..even tho it is sealed bearings. I'm on the impression that they should be noisier than stock nylon due to metal contact metal...but since its quite silent..and installed..and at a fair price at rm70...I just went with it..
One difference I notice is...it does not wiggle sideways  in the cage..where as stock one do. Googling says this may help in accurate shifting...but I'm not sure if it's gimmicky.

Etigge,
…
So, in short...the mismatch components above somehow works nicely...tho not perfect...so, for rm350 damage..seems a pretty good upgrade deal.

Thx to etigge , azum and desastar for ur inputs.

Good to hear that ! 

You know those rear cage pulley, It kinds of boggles me. Some costs as much as 200 bucks for each and they are fitted with ceramic bearings. They blowed it hard and the pulley turns and turns and stops only after some time. What boggles me is this..................How does it help? I mean the pulley is cogged onto the chains, think for a second, when the chain stops, it also stops. So, we don't really need that inertia to help.  As long as it is not stuck, it's OK, right? If you say, hub bearings , Yes, that I can accept and maybe bottom bracket bearings but pulley bearings, hmmmmm............

for me the big impact when cleaning. those aluminium jockey pulley were popular used by the mtb's where cleaning was very easy with those pulley. just fire the high preasure water and all the dirt are gone.

for below rm100 i think its worth it, but above that i think it a waste of ur money.it do improve a bit, but only around 2 or 3%. i used it before i change to sram red rd (sram red originally came with ceramic plastic pulley)

nevertheless, it was easy to clean. and i still used it at my 105rd on my speed p8 touring bike..

I too wanted to change Token pulleys when Jimmy told me that the drawback was when the chain is stuck, you might pull the RD cage off ! Because it is metal, it won't break like the plastic pulleys and he told me to use back the original pulleys. Still originals, like 105s or Ultegras, XTs or XTRs , all of them have sealed bearings as well. Same principle is machinery gearings on why in some gearing systems, one or two gears are made of nylon instead of using all metals. This is just in case if it is jammed, one will give way and not break every gears there is.

I too wanted to change Token pulleys when Jimmy told me that the drawback was when the chain is stuck, you might pull the RD cage off ! Because it is metal, it won't break like the plastic pulleys and he told me to use back the original pulleys. Still originals, like 105s or Ultegras, XTs or XTRs , all of them have sealed bearings as well. Same principle is machinery gearings on why in some gearing systems, one or two gears are made of nylon instead of using all metals. This is just in case if it is jammed, one will give way and not break every gears there is.

Yeah etigge, not sure if it has any impact, other than looks..even tho it is sealed bearings. I'm on the impression that they should be noisier than stock nylon due to metal contact metal...but since its quite silent..and installed..and at a fair price at rm70...I just went with it..
One difference I notice is...it does not wiggle sideways  in the cage..where as stock one do. Googling says this may help in accurate shifting...but I'm not sure if it's gimmicky.