Masala Bay in Uptown Waterloo (3B Regina St. North) is one of my favourite restaurants in Waterloo. I visit there frequently - their lunch buffet is wonderful and very good quality. Best of all, most of the dishes are gluten-free.
I've often asked the chef (a really nice man, by the way) about the use of gluten in their dishes and he definitely knows what it means to not have gluten. To illustrate my point: yesterday for lunch there was a new dish I've never tried called "yogurt curry", which had balls of something in with a sauce.
I asked him about the dish and he indeed said it was gluten-free. He said the balls were made from gram flour, which immediately I didn't recognize so I was concerned. (Gram flour is not a flour I use regularly or see regularly in foods, so I couldn't remember if it indeed was gluten-free).
He mentioned to me that gram flour is simply chickpea flour, which is indeed correct and is gluten-free. In fact, gram flour is a staple in Indian cuisine - a good thing for us Celiacs since wheat is therefore rarely used.
See http://en.wikipedia.org/wiki/Besan and http://www.celiac.ca/EnglishCCA/egfdiet2.html#allowed for more information about gram flour.
Anyway, my point of this story is that not only is Masala Bay a wonderful restaurant serving great food, but the chef knows about what is and isn't gluten-free, so definitely ask him if you have any questions.
As for the restaurant itself - don't expect "Curry in a Hurry" prices - the lunch buffet is $12.99 but is well worth every penny compared to 'fast food' curry places like Curry in a Hurry. Dinner is much more expensive, and quite frankly I prefer lunch because you get many of the same dishes but at a fraction of the cost.
Either way, if you've never been to Masala Bay, it's well worth the visit.