In my opinion, the MG-800 has a wider range of tonal options than the D-350, and that's coming from somebody who really likes the D-350 he uses almost daily
In response to: "I'm after a small, quiet (like the genzler) amp", the D-350 fits the bill perfectly, even a little better than an MG350 or 800 could.
I feel a Subway 800 series amp could command a stage more confidently than a D-350 given the two 350w/8Ohm cabs proposed and have capacity to add a third cab later if ever necessary. I believe the D800+ is making lots of people happy.
My solution has been a stack of two D-350, but OP mentioned import pricing being a constraint.