this is a somewhat late contribution to thisthread judging by the last post's date but one of the postees here asked me a question privately and i found this post through his profile...so i'm putting my $0.02 just in case someone might find it helpful nevertheless...
i blew up my liitle 350 rocket early 2006 by red-lining it for too long on a parkway and so i bought a 'crate' 455 to replace my poor 350 [bought the 'high-perf' 455 from some dude in minnesota who advertised on 'chooseyouritem.com...and it was a nightmare and a can of worms but that's a whole different subject hehe]...
a friend of mine did the swap [i'm a quadriplegic so i can't do jackcrap] and the mill now puts out just above 425 hp and 550 ft/lbs...
i loved the qjet on my previous mill but the intake and qjet from my slaughtered 350 never worked very well on that big block for some reason so i finally opened up a summit catalog and after parting with around $750, i had an edelbrock torker 2 and holley 4160 [750cfm - vacuuum secondary/electric choke] carb swapped onto it and that combo really works nicely now...it still peels out hard from idle but more importantly with the new combo the mill picked up some significant 'whoop ass' from around 2000 rpm and above which was sorely lacking with the intake/carb combo from my little rocket...
just relaying my own experience....
))