All about preference. I can see this quickly become a which is better thread, but when it boils down to it, it's all about what you know best and what you're most comfortable with. Getting the mounts back should be super easy provided they didn't hack up the tranny tunnel and even then the T5 would require a modified trans mount anyways (if you wanna go that route).
I really like my L6 and with a light turbo it should give you comparable performace to a SBC. I just wouldn't go back to an L24, just because L28's are so plentiful relatively that it'd probably end up the same price.
Past that it's preference. You can get a 4 barrel, EFI, Side-drafts on either motor so at this point just go with what you feel most comfortable with.