My partner and I only stayed one night at Fiddler's Inn, but we both really enjoyed our time there. We were in the Westphalia Suite which was large, well appointed, and very comfortable. It was also towards the back of the property, so it was extra quiet. Breakfast is not provided at the Inn, but we were given a voucher to use at Blue House Baker and Cafe that is just two doors down. It too was very good.
What I liked best about Fiddler's Inn is the location on a quiet street near downtown Carlsbad. Most of the hotels I looked at in Carlsbad we're chain hotels located on an ugly commercial strip at the edge of town. As we passed those hotels when driving into Carlsbad, I was so happy I had chosen Fiddler's Inn. The Inn is also close to some good dining. I recommend Red Chimney Bar-B-Q for dinner and Kaleidoscoops for Ice Cream.
My only suggestion for improvement, would be for the innkeepers to remove the handheld shower head and just install a regular shower head. The handheld would fall out of it's holder at the slightest touch. It was a bit fruustrating. Still, that said, I highly recommend Fiddler's Inn and I hope to stay there again myself.