Yeah with what you're doing to your heads it will like the 284 better. Slightly more "aggressive". Can't wait to see what #s it puts down. And for break in, as cool as that qjet looks id break it in with an already known good carb. Less time fiddling. And take a video! There's like 5 Buick 350 break in vids on the entirety of YT and mine is one of em.
Bob said he liked the 284 because it has a longer power range and it also comes on 300 RPM earlier. Obviously with the 9 way timing set, where the power range is can be adjusted.
I agree completely on the carb, I don't want to have to adjust it while simultaneously breaking in the cam and setting the timing. I too have noticed there aren't a lot of Buick 350 videos on YT, I'll try to have someone record it.