It's not that simple, as I keep saying, there is a sizeable community of us whereby they can't get a acceptable grinder, due to various valid reasons
1) Kitchen space
2) Preparation and maintenance time
3) Cost, for the sake of discussion, let's agree that any grinders < RM 500 to be unsuitable for grinding consistently. I think you'll need a minimum ZD16 grinder? Around RM600.
4) There's a lot of users out there who is using subpar grinders, < RM 200 grinders out there.

For those that fall into the above categories, we just need to work within the constraints of what's available to us, and I feel that's where pre-ground coffee by your roastery can be acceptable. I'm not talking about buying pre-ground from tesco etc... where their 'pre-ground' is not intended for expresso machines at all.

Don't just keep saying must use grinder, must use grinder, as it may only encourage more people to buy subpar grinders, which I think we all should agree is worst for the end result.

In my own research on this topic, my general idea to solve the problem for people like me is

1) Buy maybe 200g from a reputable roastery, preferably your own neighborhood roasters, tell them to grind for expresso machine. You get the benefit of customizable grind size, as you build the relationship with them
2) Ask them to take note of their 'extra fine' grind size, if they're experienced, their 'extra fine' should fall within +- 10% of your machine's,
3) Pull your shots, if it's over extracted (too fine) -0.x to 3g to your recipe. It's its under extracted +0.x to 3g to your recipe.
4) Repeat until you get a shot that's acceptable, (due to our constraints, we accept the tradeoff for time, cost, convenience against the perfect shots)
4a) If the +- of grams don't work, then you can +- temperature of your expresso machine, (if it's programmable)
5) Note down that their current grind setting is too fine or too coarse.
6) Go back to them to tune their grind a bit more for you the next batch of pre-ground.
Rinse and repeat few packets, and eventually, you'll get to a point where, the pre-groud is good enough.
While I appreciate and I do understand why we should grind, (I've used grinders before) there's just those of us who can't and we need to do the next best thing that's available to us, telling us we should grind our own, or how each pack of new beans need to be dialed in, that's not gonna work, or worst, it encourages subpar grinder purchases.

I'll go ahead with my plans and see how it works out, if it does end up with an acceptable shot, this is something that I feel could really improve the experience for a lot out there, especially those that are currently grinding with subpar grinders (those ~RM 100 ish grinders that I see a lot is using)

It's been a few weeks, and I'd like to add in some comments on how my experiment went.

I got a bag of extra fine from SOL roastery, via shoppee

1st 3 of attempts was overly under extracted, as I was tampering too weak i believe. Getting 4 to 7 bars of pressure as i increased the dosage.
4th attempt, at 18g, I got about 8 pressure, and the flow is still quite fast, ended up with ~40g at around 15 seconds.

5th attempt,
1) 20g of coffee powder
2) Even tampering, with a leveling tool, and sufficient force of tamper.
3) Extraction time 23-26 seconds? I didn't really time it to the dot, as I wasn't expecting it to go well yet - Check
4) Pressure, ~9-10 bar of pressure using unfiltered portafilter/basket - Check
5) I got 41g of extraction, for my 1 to 2 ratio - Check.

Mathematically, the expresso hits all the correct numbers.

Moving on to the taste test, it's good. Not overly sour, body's good, not overly bitter and I can even get a lingering sweet  '金' after taste to it,
Crema's sufficiently there, the coffee could have been fresher admittedly, but that's my own problem as I only started brewing with the expresso machine couple of weeks after my pre ground has arrived.

But by all means, it's actually a workable routine. 

If you're using those free grinders with your gemilai, or those < RM 300 grinders, going for pre ground coffee, from a roastery that freshly grinds and ship to you, is actually a much better experience and I encourage you all to try, don't get discouraged by those who say you must grind yourself, without understanding fully the grinders that you need to buy to be able to home grind, you will literally destroy your fresh precious costly coffee beans live with subpar grinders!

You will
1) Save time from grinding your own beans, faster cleanup.
2) You will get a much better expresso shot, as you will get an even grind size across your entire pack, getting an even grind size is actually a more IMPORTANT variable vs how fresh your beans to grinding is.
3) You don't have to invest RM 600++ or over thousands for a grinder that will take up kitchen space and maintenance
4) Less coffee wastages, from dialing, throwing the 10g of coffee from the old settings.

I'll add in a video/pictures later.

It's been a few weeks, and I'd like to add in some comments on how my experiment went.

I got a bag of extra fine from SOL roastery, via shoppee

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Hi all, I am thinking on investing in a coffee machine. Currently looking at three options breville basrista touch(semi-auto) and delonghi dinamica plus and dinamica ecam 350(fully automatic). May I know taste wise is there much difference between semi auto and fully auto ? And if possible just want to know more about the machines

hi guys, anyone here using Monin syrup for their coffee? i want to try the Monin, but just try the 250ml. 700ml seems too much for me. i want try different flavour. can 700ml pump version fit the 250ml?

Hi all, I am thinking on investing in a coffee machine. Currently looking at three options breville basrista touch(semi-auto) and delonghi dinamica plus and dinamica ecam 350(fully automatic). May I know taste wise is there much difference between semi auto and fully auto ? And if possible just want to know more about the machines

I'm not sure anyone here does... if you wanna try just go for it

personally I hate flavored coffee... shop uses this trick because they use cheap low grade coffee...

It depends on individual. Some say they hate latte because it is not a pure coffee aka espresso. And not all ppl can drink espresso. I just want to maoe sure the pump can fit, if not i will waste my money

What about automatic machines?

Can stretch my budget to rm3k

If you are interested I got an old Jura Ena micro 9 for sale. I bought it 4 years back but only use it for less than 6 months. Then in to the storage. I now only use semi automatic Breville BES920. Frankly speaking semi auto still taste better than fully automatic but if you want fast and easy morning latte, this is as good as it gets.

If you are interested I got an old Jura Ena micro 9 for sale. I bought it 4 years back but only use it for less than 6 months. Then in to the storage. I now only use semi automatic Breville BES920. Frankly speaking semi auto still taste better than fully automatic but if you want fast and easy morning latte, this is as good as it gets.

Hi, I have been brewing filtered coffee for a few months already. I always hear people mentioning "sweet" in their coffee. However, I do not really understand that because I just do not taste sweetness in my coffee. I initially thought that I brew it wrongly. Hence, I ordered pourover coffee from other cafe and I still do not taste any sweetness. The closest I ever tasted "sweetness" in my coffee is when I breath through my mouth after a sip or drink water/salivating after a sip. Is there any layman description for sweetness in coffee?