I'm glad that I work for Ashcroft ... I can watch them being made and calibrated.
We have made thermometers and put grill maker's gauge faces on them in the past.
I would say TelTru's are the best but they are kinda expensive compared to the others. I've used River Country and they work very well. I did try out the glow in the dark version, as well, and the only thing i'd say about those is that they don't glow for as long as i'd wish for them to glow. They do hold temperature readings well though.