http://www.performancedistributors.com
If you have used them what do you think about them compared to MSD and other distributors.

That big cap GM style HEI is immense. I used to run Chevys for years so I am familiar with the cap. With small blocks, its impossible to fit easily in an A body without denting the firewall. B and E bodies would clear. Trucks too.
The Big Block version used to require mods to the RH valve cover, especially Hemis to clear the distributor body. They may have made changes, but then it would stick up higher, right? A HIGH rise distributor? Uhhh... I'll pass.