I overlap the face frame about 1/4" on the wall side and scribe it to the wall, takes a little more time, but looks way more professional. Using trim there instead looks like a homeowner job(IMO), and how do you address the molding at the top and bottom with cove?(more homeowner job appearance)
There is a bit of work fitting a cabinet(properly) to a corner.
Most corners aren't square, and there is typically some mud build up in the corner as well so they are a bit rounded. Overlapping the face frame helps move you out a little from this, and gives you a little margin. Otherwise you might be dealing with up to a 1/2" gap or more. In some instances I will still have to ease the back edge of the carcass to compensate for mud in the corner, and for out of square walls.
Depending on the walls, and the cabinet style, I might also cut the back in a little deep which leaves some material to scribe on the area by the door that will be visible.
This is the difference in Custom made, versus buying boxes and using trim to cover up the poor fit.
Last edited by shoot summ; 08-18-2015 at 04:31 PM.