Thanks to all who responded to my inquiry yesterday concerning Sette Mezzo, and especially to Jacqui for the specfic recommendations.
Overall, on a scale of 1 - 10, I'd give this place a 4 or 5. The chicken special Jacqui's husband likes so much was very, very good. The other dishes we tried were fair to middling. The service was good, but I found the room itself wanting....very crowded (I can't understand why). The wine list was good, and our waiter at our request chose a bottle for us (I am no wine expert anyway, but don't know much at all about Italian wines. I'm okay with the varietals, but not knowledgable enough to order wisely, as I would be with California or French wines.) Anyway, no one liked the wine except me--not sure what that means.
So, I think if this restaurant was in a suburb and tried to charge the kinds of prices we paid last night, they'd go out of business in short order. In Manhattan, where mediocre high-priced Italian food is the rule (and there are exceptions which prove it) I guess Sette Mezzo is totally safe.
Oh, and by the way--the cash-only thing? turned out to be no big deal...our hosts knew about it.