Hello, I've applied for the same courses and a lot of the same unis, so I may of some help (If anything through empathy rather than knowledge).
I had the same dilemma between Glasgow and Dundee, they're both really good courses, so it came down to other factors. I ruled Stirling out fairly early because it's just not quite as good as the rest, and I think Napier is a little bit less prestigious than Dundee and Glasgow.
I've visited both and I preferred Dundee as a city and a uni, so I accepted my offer from there. It's also a whole bunch cheaper to live in than Glasgow.
Both are really nice though, so either way you'll be on a great course in a great city.
Hope that helped a little.