The food here is inconsistent, and seems to have gotten both hotter and less tasty every time I visit. To me, brute force heat is not a good substitute for complex spices and flavours. Also, expect slow service if not ordering from the buffet. They are expecting people to get a dosa, some soup, and some buffet items.
The building itself is also really humid and stuffy - wet windows, something that is rare in Calgary. Southern Spice has heat problems in more way than one.
This is one of the few places to get south Indian and dosas in Calgary, so even though it could be better, I do go here occasionally (although not recently).
Cons: Food too spicy (heat), Hot building, Slow service if not getting buffet items