Tehran is a wonderful establishment.
I've been an infrequent visitor for the past 10 years. I always wish I'd go more often.
The menu doesn't have too many options. But the choices you have are so flavourful that you won't feel lacking.
The plate sizes are quite large, though I have noticed that portions decreased a bit recently, and prices went up. Worry not, you'll still be stuffed and not spend too much.
Everyone should give Tehran a try. The food is delicious and the service is quick. And shame on someone rating a restaurant they've never been to and making a judgment based on hearsay.