Reason being, is that after the age of like 10, I stopped asking questions and looked up answers for myself.
Now with that said... have you looked into the 15+ other topics on these same questions?
No firmware is "outdated", do you know much about PSP Hacking? If you don't I would go to psp-hacks.com and do a little downloading then reading on google.com about what everything is.
I wouldn't get a PSP3000 as they aren't fully hackable, while the earlier non TA-8X PSP2000's are hackable and slim.
All homebrews and other "legal and illegal" applications work for all models, but you'll want to install 5.50 GEN D-3 to play all games.
However you can't play new games that require 6.10-6.20, as the 5.50GEN D3 firmware can only hack up to 6.10-ish, no higher. If any of this confuses you I would look it up. This also accounts for retail games, as you'd have to use the time machine application to upgrade to 6.20 firmware, then back to your 5.50Gen D3 custom firmware.