A lot of guys run 2 because they didn't place the 1st one right to begin with. One properly placed gate, sized correctly is fine for most builds. Google optimum wastegate placement to get some ideas.
That being said, I have 1 60mm on my build and have some creep issues because of placement. I'm rebuilding my crossover this winter and going to 2 smaller gates that are vented to atmosphere, instead of into my downpipe.
[email]Rick90lx at yahoo dot com
93 coupe, Holley Dominator EFI, 9.0:1 383, Highports, 80mm turbo, TH400