RE: improved vibration
Well its hard to tell from the distance, and even harder to compare vibration levels.
Here is a pic from the installation of the 120 SP in my Chester Jeep. Its not ideal since the firewall is supported from only 3 sides due to a big hatch. Firewall is 6mm ply glassed to the fuselage. The firewall is sandwiched between motor and the alu backplate.
So that works fine, its rigid enough.
Cheers
Andi