What CFW are you using? I have never had any issues with 3.55Kmeaw (aside from the normal issues of newer games and PSN access, but all the CFWs have these issues). All the homebrew worked very well. The only other one I almost tried was Rebug since it seemed to have more active support.
But most of that seems to be with regards to spoofing (I could be wrong, but I haven't been keeping up very well since I updated to 4.10 OFW on my system). My friend's PS3 that I am babysitting while he is out of the country is on 3.55 Kmeaw. Again no issues on his either. Unless a new CFW that can do 4.11+ I would say to stick with what has worked for you.
The only CFW that I am aware of that is 3.55 and might have issues is the Geohot one since it was supposed to only allow homebrew and not game backups. Some homebrew I believe has to have special versions to run on that as well. I think Showtime Media Center (or whatever it is called) was one such brew.
And unless anything has changed on the weird 3.56CFW, I would stay away from it since I seem to remember it not allowing you to use any other firmware after it has been installed. All-in-all I think that most of the CFWs basically do the same things. If some brave hacker releases a newer CFW (after getting one to work), then I would worry more about changing what you're using. But that is just my opinion.
3.55 Kmeaw (Safe and popular)
3.55 Rebug (Constant support and updates)
3.41 any CFW (this is the most vulnerable version and easiest to hack, but little ppl are on it so it doesn't get support or updates)
been on REBUG since I hacked my PS3 into CFW. So REBUG is the best CFW for me, nevertheless about the RSOD, as long as you don't mess with the firmware (aka install some modification and what'snot) you're safe for it.
I started in the early days with psbreak 1.2- 3.41 hermes b-and currently am using 3.41 hermes v4... the reason that I don't update to 3.55, is that I simply don't have the courage to re-edit all the fixed eboots of my game collection (retail & psn)
afterall the games that remain ''locked'' for 3.41 cfw are very few... since I don't have the slightest interest of a new dongle, and being just an end user that seeks only game experience, I can say with no doubt that the best cfw for me is 3.41 hermes v4 ...