If 9 months old then sure can claim warranty, you should consider yourself lucky that it happens within warranty period. Pre-Geely Proton models are famous in parts failing after warranty

I've done changing och twicem both at SC. First time was I kena och burst and had to call a tow truck (I was clocking at 50k km then), and second time was when I do 100k km service.
I think you would be fine if do at either SC or outside. But I suggest to change it when you are doing a regular service so you change the engine oil at the same time.

The fastest 0-100km/h Proton was Satria GTI, 8.5 seconds. If I remember correctly Suprima S was 9.9 seconds, slightly behind Preve 1.6 CFE 9.6 seconds (likely due to 17" vs 16" rim & broader tyres).
In terms of performance, I haven't seen a good comparison on Satria GTI vs Suprima S yet.

Yes, that's official datasheet. Normally official data is under specific condition so people results maybe different because the road condition, load weight, wind speed, inclination/declination, tyres, engine condition, etc. will be different. Even the same car under different condition will give you different result.