Probability of despawning after 1 second:
60 fps- 63.5%
40 fps- 63.7%
20 fps- 64.2%
10 fps- 65.1%
5 fps- 67.2%

I thought milliseconds meant milliseconds of game time, not computer time. Under most circumstances, that line should perform fine. I'm not sure that it would ever be a good idea to skip that many frames. The player would be out of control.