Not true at all at least for my Non-jailbroken 3G. I have had that happened twice (in a row) but the 3rd time it worked perfectly. That's out of like the 20-30 times i have launched the app. It performs smooth enough and impressive graphically (nearly identical to the PSP version).
i have not rebooted my 3g in a while and i installed gta and played it for about 3 hours till my battery died and it ran smoothly the whole time.
