I dont trust auto installers with my PSP, I think id cry if someone wrote an auto virus installer!!! glad to hear you got your SE-B'' running, its great for brew and emu's, not sure about the rest of it though, have a search around for an answer.
The recovery mode alows you to recover from partial bricks, although im not sure how as i havent had to try it yet (touch wood :) )
It also lets you turn off he sony load screen and some other bits and pieces.