actually west coast BoS is not really good at all, they are very self serving and elitist. Also just because you are evil does not mean you can't be on good terms with the brotherhood, right? after all in the new game, karma and reputation are two different stats now, so it is entirely possible.
Well if you killed the BoS and got the armour from them they use as hell would not help you. They would shoot you on site. If you got the PA in some other way they might help you (If they don't shoot you for your PA) but you would have to do something for them. Kinda like FO3 but again that was annoying and was at the end of the game. That's why they give you PA training just by playing OP because alot of people complained. "I finally get PA and the game ends!"
I don't want to help the BoS by doing something simple like getting them X amount of lazer weapons. I want to have a really long quest.
Could have the BoS to train you but why not find an old PA wearing program in a military computer or a manual?
Why is ps2 bos despised so much? I never hear good things about it. Is it worth playing?
Because of numerous inconsistencies with previous Fallout games, Fallout: Brotherhood of Steel is not considered part of the official Fallout canon, however some of its content could be used as "flavor" material.