I agree with you about the pretentious thing, but only about the Arcade Fire, ironically enough.
One of the most obnoxious things I ever saw was the lead (don't even know his name) performing on SNL the song "Intervention". Dipshit had the nerve to SMASH his instrument after the song. Listen to the song. Then imagine some jackass smashing his instrument after performing it live on national television. Yeah.
As for "too ambitious for their own good," can't agree with you there. When has ambition ever been a bad thing, especially considering how prolific Spencer Krug has been?
Do yourself a favor, get some Handsome Furs at least. I seem to recall mod really liking them (not that that means anything

). I saw Magic Weapon live (opened for Sunset Rubdown). Very impressive on first hear, and that's an accomplishment considering how hard it usually is to take in unfamiliar music live.
(Hey, neon -- haha, after all this time, you're still neon.) I wouldn't know about the two you mentioned. I've only listened to BSS briefly and never the other one.