changeable/removable custom firmware?

It's been about a year for me since all of the new homebrew, so i'm out of style lol. ok thanks for the explanation. Just to let you know ACE, I have an original fat psp 1.50 with a couple of emulators, roms and an iso loader and also a slim that i bought this week. I don't think I can run the more recent iso's like final fantasy tactics/jeanne d/arc on my 1.50 even with an iso loader right? I need up upgrade to a cfw. Also, does custom firmware mean i can put 3.71m33/3.52m33 on my 1.50(but theoretically keep 1.50) and then change it later on too another advanced firmware whenever it comes out? I also have a non-sony magic gate 4gb mem stick. Is that a problem? Sorry for all the questions. thanks in advance for the responses.

[ace]

Yea, you can upgrade to a custom firmware on your 1.50 and still be able to upgrade to a newer one in the future. All a custom firmware is like the official firmware it is, but can run any homebrew like 1.50. It's like a hybrid between the official firmware & 1.50, along with a recovery menu incase you semi-brick your psp after you have upgraded You can also use your 1.50 after you upgrade to a custom firmware to also make the pandora's battery and change the firmware on your slim to a custom firmware. Also you no longer need an iso loader to load ISO's. Just stick them in an ISO folder on the root of your memory stick and play them
And no, as long as it's not fake then there shouldn't be any problem with your mem stick.

Awesome, that was a big help. now I just gotta upgrade me 1.50 and i'll be all set. Thanks man.