just so you know i wouldn't go with the demon carb, those things are a real pain to get running right, even good tuners have trouble getting them to run right...
OK, so what's the big difference between a Demon and a Holley other than the metering blocks are billet and not porous castings. This makes them "a real pain" to tune? Horse Cookies!

Do you have any personal experience with them?!

Or are you (more likely) just passing along some anecdote you have heard somewhere along the line?

Kitz