I really enjoy Blissful.
The instructors are helpful, even for a newbie like me. They are patient and take the time to make sure you are getting the benefit of the poses while making sure you don't hurt yourself.
Their on line booking system is easy, and when I've dropped in I've never had a problem getting in.
The classes are not over crowded. The studio is clean and modern.
The only downside is the price, its a bit steep, but you get what you pay for.