I don't want to be a CFW salesman but I think it's fair if you get testimonials from people for whom this option works to balance it with the negative.
I was strictly a Hermes payload player. PL3 would cause all sorts of problems to my system and eventually after trying to delete a bunch of games unsuccessfully, I reformatted my HDD (actually, I upgraded to a larger one at the same time), and installed Kmeaw's 3.55CFW.
Now I have all my old games back (minus some saves I forgot to back up or backed up incorrectly), and I don't have to do the button thing and I don't have to remember to eject the BD when I power off.
Plus, I can play POP Forgotten Sands now! Woot!
Also, I have GT5 running and have been playing it with my logitech wheel - sweet as!
All the games that played before for me play again. I only had one freeze (with POP trilogy), but when I rebooted it played fine and I haven't had a single freeze since.
The other thing you might consider is where is this all leading to. 3.50+ did take away stuff just as the firmwares after 3.15 did. Will there be a universal CFW? Will there be a better one if you base it off 3.41 rather than 3.55? There certainly won't be a better one based on 3.56!
Well, if 3.41 turns out to be better for any reason in future, guess what? You can downgrade to it from 3.55!
Now, granted you have to be careful with any change in FW and it might go pear-shaped on you for any reason (look, the forum's full of them), but the grass really is greener on the other side!
My two cents..
"We all agree your theory is crazy, but is it crazy enough?" - Neils Bohr