Originally posted by Vessel
Getting a .55 CFW PS3 is only scratching the surface of what you must do to get online and start modding. DEX firmware is better and obsolete is so many ways that many can't be expressed. It runs smoother, less ban risk, Better options and many more. You must go onto a custom firmware after being on 3.55 and from there you can choose any CFW you want ie; ITA, Rebug etc. I prefer ITA personally. This is basically answering your question +more so hope this helped.
You are Correct. ITA For life :p. Also obsolete means out of date , no longer useful or relevant, So i think you used the wrong word.