First of all, please note that it's never 100% to play any game online on a modded PS3, however in the overwhelming majority of cases people got banned not for just playing online on a modded system but rather due to using game mods (i.e. cheating) online or attempting to sync hacked trophies. As long as you disable syscalls / unload HEN and play legitimately then PSN is relatively safe, although as said before, it can never be completely safe.
Having said that, there are a...
Do NOT play the following games online if you don't want a ban!
Having said that, there are a...
Do NOT play the following games online if you don't want a ban!