I've noticed on small commercial buildings that residential cans are installed. Instead of romex, MC cable is run. Recently I changed some bulbs on a job and wrote down the model of the can:
http://www.junolighting.com/product_detail.asp?ino=2171&Sel_Id=1706&brand=1

Is it okay to install a residential can and what is the difference? Is it mostly up to the architect?

Thanks,
Byron