I have indeed been there once. It got a favorable review in the SF Chronic'e's East Bay Friday section about a year ago.
I have to say I wasn't blown away by the food, or maybe I'm just not really fond of Tibetan/Nepalese food in general as I've been to Kathmandu on Solano and thought it was okay - interesting culinary-wise to say the least, but nothing special. I think Kathmandu was a tad better than Cafe Tibet as well.
Our favorite thing after sharing appetizers and entrees was the el cheapo $2 potato appetizer. The $4 potato fried cake appetizer wasn't very good. However, the service was very good with our server who was very charming as well.