The only thing that sways people from them is that cost and traction/weight issue
Traction:
I had very little traction issues with mine, I ran 28 x 10.5 MT's slicks, southside bars upper and lower, air bag in right rear,
pinion snubber(the best weapon EVER and very few use an adjustible one), and of course subframe connectors, 8 point cage, 90/10 and 50/50 lakewoods.....stock (1979) 4 cylinder springs in front and 1990 model GT springs in rear
My best 60 ft was like 1.28 or something, I'll have to dig out a timeslip!
And of course if I didnt do a good burnout, or if I used the 150hp nitrous it would have a few traction issues. BUT only if I tried to leave the line with the Nitrous flowing!
weight issue:
I used aluminum everything in the front. Alum. waterpump, heads, radiator (actually radiator was to big for 1/8 mile drag racing, to much weight per pounds of water), alum. bracket for my fiberglass hood (lift off) then of course I took off my power steering, used a manual rack (stock on 81 model), removed my brake booster (manual brakes per 80 model junk car), alum. Vic jr intake, removed front sway bar, skinnys on front 3 1/2" wide, 4 cylinder brakes on front, removed all my heater/ac stuff, all my undercoating, spare tire, hood latch, hood latch cable, front bumper support, front bumper shocks, rear bumper shocks, rear bumper support was home made, removed hood hinges, removed inner fenders, removed EVERY thing that wasn't "Just Having to be there"! The car when I finally switched it back over to EFI and back to a 5.0..........weighted over 200 and something pounds light at bowling green when I went to race in NMRA in 2000! and that was after going back with power steering rack etc... The car was really really light compared to what you would think for a Big block car.
just take weight of 460 engine and subtract weight of 302 efi and then you have the weight you would have to remove to make them the same.......basically what I did.