We have found Os to be a bit variable. We have had some terrific meals there and some pretty poor ones. Given that they are pricey, we are shying away from them for the time being.
We are now opting for Canoe in Center Harbor. It is the sister restaurant to Os and the food is more consistent and the prices are lower. They have a number of the same signature dishes that Os does (Lobster Mac & Cheese) and every meal there has been consistently very good.
We also like Lyons Den. They have a terrific view, reasonable prices and have been consistently quite good.
Just my 2 cents.
Jetskier