Designing Kitchens and Bathrooms - Glass Mosaic backsplash question

Hello all,
I'm in process of remodeling our kitchen and one project is putting in a glass mosaic tile backsplash. The old back splash was glued on laminate.

I've ripped it off and there is plenty of glue residue, torn drywall paper etc. My first thought to make a good substrate for the glass was to install a 1/4' cement backer board and screw to studs. I think this will work fine, but have one question.

Wherever the backsplash ends, what is the right way to trim the edge? At the end of a run, if you look at the edge there will be the tile edge and you'll also be able to see the edge of the backer board.

Make sense?

Other thing i thought of doing was cutting out drywall in that area, furring out the studs by a 1/4", then installing hardi backer in the cutoout so it's flush w/ drywall. That seems like a real pain if there's an easier solution to the edgin.

Thanks
Marshall

Since this is a back splash why nut just cut out the damaged drywall and replace it with new drywall? This is not a wet area so drywall will work fine. Just follow the instruction for setting that glass tile because sometimes they specify a certain mortar.
As for the seam, just overlap it with the tile or find yourself some nice trim pieces and border the glass tile to your liking.

I just tried the new metal edging strips for my new tiled wet bar - they come in a variety of finishes/colors - and while a bit spendy - they look great - requiring no bullnose edging of the tile.