Do people use HEI distributors on their 455? We will be putting a 455 in our 70 Cutlass S

 

I have one on my 70 W30, to me it is the way to go.

 

I think this is similar to the drum vs. disc brake debate. A drum system, when correct and finely tuned, is virtually as good as a disc system. But it's a lot harder to work on. Same story here. HEI is simply easier to work on.
Just make sure you don't use the current (as in "original") power feed wire. You need to run a full 12 volts to an HEI. IIRC, I used 12 AWG wire directly from the "start" terminal in the fuse box, through the firewall, and to the HEI BAT terminal.
I'm working on my advance curve right now. But I got two different kits, an MSD and a Mr. Gasket and accidentally mixed up the springs! D'oh!

 

The Hei is a pretty simple upgrade. As Mac said it requires a full 12v keyed source. You can replace the resistance wire or run a wire from the IGN terminal in the fuse block. The other thing to note, the original timing specs for the points distributor are N/A. There are many threads on here and articles on the internet on how to set one up.

 

That's it; the IGN terminal. I knew I didn't have it quite right. Thanks for the correction, Eric.