Dave, I have an older MachOne which Dennis has installed a new-design rib. I have also had the DeVault folks build a new stock for the gun to fit me.
Pro's??? Theres a ton. These guns point great, shoot "without" felt re-coil, never break-down, made in the USA!!!
Con's??? Well, to be honest very few.
The MachOnes are a heavy gun, but I like that (could be listed in the "Pro's"). Controversy??? lock-time is the fastest in the industry, again, could be "Pro's/Con's. Shoot one for yourself and see what you think.
The new Infinity from DeVault's is lighter than the MachOnes were, and they have even LESS-felt re-coil. (hard to believe).
Are you thinking about giving one a try?