You should confer with the people who are so upset with their tile installation. Looks like your tile is not straight either. Perhaps this is to make it look more hand done.

I like to use a vertical metallic "pencil" as an edge to glass tile when I have an open ended backsplash. It is neat, unobtrusive and contemporary in nature.

This might be helpful.
http://designernotes.modwalls.com/2011/03/03/edging-options-for-modwalls®-lush®-and-brio®-glass-tiles/

Look up Schluter Systems.

Hi Ckerst,

We've typically used pencil mold as Toni suggested (if you can find one that matches your glass tile, choices are limited) or Schluter edging as KOH mentioned, but you can also polish the edges of the tile if you're looking for an even cleaner look. Your tile installer will need PVA discs on a grinder for this, or even carbide belts (starting at around 400 grit and higher) on a belt sander. The finished look wont be exactly like the face polish, but it looks very convincing.

Steve