Had a Freedirds burrito today. Like Chipotle, it's not as good as they claim and overpriced. So here's my laydown on those upscale fast food joints.
1) Lower your expectations. In general, they don't taste as good as their cheaper fast food brethren.
2) Do bring an appetite. The entree is usually much bigger hence the higher price.
3) Don't bother with chips unless you like to overstuff yourself.
4) The staff are generally from the wannabe 'chic' crowd. Pompous with attitude. Expect flak if you give them any trouble such as slowing down the line, etc.
5) Research and decide what you want BEFORE entering the store. See above. :p
Seems these upscale fast food is more of a fad than anything serious. They don't have any food really worth the higher price. Only exception I found of the ones I've tried so far is Wingstop which actually has pretty good food. Not very healthy though so you shouldn't eat there often.