I don't know why I didn't write a review earlier. We really enjoy the Studio B Buffet at the M Resort. We go at least once whenever we are in Vegas. Even though the M Resort is off the strip, the line up for the buffet especially for the seafood buffet on weekend can be verrrrry long. The food quality is top notch, except for the sushi. I don't care for it since the sushi rice tends to be too cold. The mac 'n cheese is one of my favorite dishes here though they tend not to serve it when they have the seafood buffet. The prime rib is good too since if you are patient, you can get a medium rare piece but they disappear fast. My last trip out I had the seafood buffet comp'd so I really indulged in the fresh oysters and the crab legs (which I am glad were not salty).
They have a really good assortment of desserts but my favorite is the ice cream counter.
Service is generally really good to excellent most times we have been. The wait staff works hard at clearing the tables and getting drinks.
Definitely recommend Studio B if you want to wander away from the strip. M Resort also has some really fun slot machines to play before and after dinner - BONUS!