I have P4-PP now. I'd like to get some opinions on whether P5 or P6 is the better program. What items would be useable from P4, can I use any P4 stuff at all? If I had P4 favs would I still need to keep P4 in my system to use them?

I know P6 is the latest version, but is it really better than P5? Are items from P5 useable in P6, and vice-versa? I know these are a lot of questions, but, I can only afford to invest so much money in new stuff.

Any help given is really appreciated. Thank you, all.