I used it on my small block 350 in my 69 Camaro and it worked great. This was a long time ago but what I do remember is that it was easy to setup and a really made a big difference in terms of drivability. The other great thing was that all the finickyness that comes with owning a carburetor was gone once and for all.
I can't recommend the Holley Sniper EFI enough!