We love this place, and have gone on almost every trip (it's DD's favorite!).
The prices for a TS meal are reasonable, and the sandwiches are quite big! I usually get some sort of sandwich and onion rings, and have a hard time finishing it! The prices aren't much more than a CS place if you stick to sandwiches.
We've always found the quality to be very good.
We are on the QS plan next trip (free) and may decide to do a walk-up and just get a snack, but we're waiting until we get there and see how we feel. With the QS plan in place, it is probably going to be enough food for us, though.
Since you have the QS plan, I think you'll have to decide if you will use all your credits. If you feel you will use them anyway, not wasting one, then I would go ahead and dine there. It is super cute, and last trip our waitress was amazing!!! I agree it's somewhere that you have to go once at least!
I don't know if it's cool in there, or it's the fact that it is dark in there, but I always need a little sweater. It's a very nice break from the heat.