Considering Holley sniper EFI for my 1969 340. Thoughts from people who have that set up?

One more recommendation - given the chance to start a new system again, I would use the new Holley Power distribution block.
It would make installation a lot cleaner and eliminate the usual problems that a lot of people have.

https://documents.holley.com/frm36866.pdf

Apparently it also works on Sniper 1.
Completely agree with this suggestion. Wish it was available in 2019 when I first made the switch, would have made my life much easier.

I actually bought one recently to use with a Terminator X system but for various reasons it’s not compatible. I’d be willing to sell it if someone wants it.