Even I haven't played with the paddle shifter much, because the basic performance is already very good, kudos to Proton

The operation of the paddle shift of the Preve Turbo is crude and quite useless due to the gear ratios that are fixed too closely to each other. Nevertheless, I still use it in my everyday driving as I prefer the manual gear shifting than D in low speed acceleration.

It depends on what you mean by it's more "efficient" if the gear is left at D or S. Automatic transmissions are purely for convenience as you just step on the pedal and don't need to worry about upshifting or downshifting the gears, as in manual gear transmission. The only reason I use the paddle shifters instead of leaving the car in D is I don't like the throttle response of the car when accelerating from standstill or during low speed acceleration. There is this dragging or heavy feel of the car when accelerating from standstill or bumper to bumper crawl traffic jams. You need to step on the pedal more if you want the car to move forward, otherwise the car wont' move forward. This lag in the acceleration due to the throttle response coupled by the engine roar in D gives the heavy or dragging feel of the car.

When using manual gears, accelerating from gear 1 or 2 is more instantaneous. There is less drag or "heavy feel" during acceleration from standstill with the paddle shifters(manual gears), and the car feels lighter.

But in terms of performance as in quick acceleration off the blocks from 0 to 100km/h, the D is much better. YOu can feel the Turbo power kicking in if you accelerate the car in D. The car seems to accelerate slower if you use the manual gear shifters, as if the Turbo isn't working.

FWIW the paddle shifters are only practical for speeds of up to 80km/h. The RPMs are above 2000 at the highest gear 7 which isn't economical. I use the manual shifters all the time when the vehicle speed is 80km/h and below. I only switch from manual to D whenever the speed of my car is above 80km/h, or when I am on the mobile phone.

If you have driven the Honda City, then you would have an idea on the difference in throttle response between the City and Preve Turbo when accelerating from standstill. Although there is still a very slight delay in the City when accelerating from standstill, the responsiveness is better than the Preve Turbo. Just a light step on the accelerator the car will move forward. Unlike the Preve where you cannot lightly step on the car but put more force on the pedal before the car will move forward. Nevertheless, when it comes to acceleration power, handling and driving dynamics the City is no match for the Preve Turbo.

Spot on this one, the delay in city on startup is higher than preve. The "more force on the pedal" in preve vs city can be really see when going on hill, my city will just automatically rev higher in order to maintain that particular speed with the same pedal input whereas preve you had to push in further more to get more out of the engine and maintain at that particular speed.

It is sometimes difficult to describe the experience in words unless one has driven other cars and compared the differences. The delay or lag in acceleration when accelerating from standstill may be minimal or not so much of an issue. It is the combination of this lag and the "heavy dragging feel". No doubt the car is accelerating well, but you feel some force is pulling the car back when the car is accelerating, which gives this "dragging feel". Perhaps it is the characteristics of the CVT gearbox in the Preve Turbo. The Nissan Sylphy's CVT does not behave the same way as the Preve Turbo although there is a lag in acceleration during standstill ie. accelerating from 0km/h. Although there is an approximately 0.5 seconds lag when you step on the pedal (before the car gets moving), you don't experience the dragging feel as in the Preve Turbo. The car just glides forward and it feels light.

I not sure if the newer torque converter Jazz/City would feel as I did not test drive it but what i can saw is the overall feel on cvt is preve is better than my city for sure  Maybe one have to get use to the different cvt feel   

No experience with the Suprima S though I have read it drives better than the Preve due to upgraded electronics and stuff.

Personally I think the biggest weakness of the Preve Turbo is in the transmission. If Proton can improve on this aspect it will be a much nicer car to drive especially when it is stuck in traffic jams. Don't get me wrong. THe car drives well as it is if someone does not compare it with other cars. Only when you drive other cars you will feel the difference. But at a price of between 65k to 69k, one cannot complain too much as the car is already considered to be a good value and unbeatable at its price point.

How I deal when stuck is traffic jam is to put D and let the car creep by itself before i press the pedal. When on hilly part is just put handbrake and put D and wait for creep before drive it (think it like the hill start stop in driving test).

Value wise like you said it really a good deal apart you need to pay more for fill up but that is some marginal disadvantage to it. Pity many ppl scoff it off because of the Proton Badge infront (eg my mom ). I just wish they release the manual CFE version asap since i tend to keep car for many many years less thing to worry about breaking down eg cvt gearbox. And for the same price i rather get this than Iriz premium manual even though i do no need such big car at this stage