I know people that swear by these engine/drives. Does anyone have an opinion about these in Formula's, specifically the 370SS. I assume the performance #'s would be similar to the Mercruiser 496 HO and I know getting them serviced can be difficult in some areas. How about resale value? Any thought's would be appreciated.

Boat testers seem to like them.

http://www.boatingmag.com/boats/formula-370-best-wishes
http://www.boattest.com/oem/386/boats/125/0/off

I have two brand new 8.1 GXis in my cruiser.
No complaints so far from me.

The only issue I know of with the Volvos 8.1s is the fuel pumps.
The earlier models had the inside of the fuel pump painted, this paint eventually flakes off and plugs the internal filter.
Those who don't know better pay $1100 for a new fuel pump.
Those in the know take it apart, clean it out and go again!

Red or black?
I think black ( Merc ) probably has the better long term resale value, but red looks good in the engine bay!