No idea why they assign a 227B and a 227A. It causes nothing but confusion when it comes to fans trying to find their seats.
227A sits a little closer to the infield but other than that, both sections are essentially the same. Both are on the third base side and allow fans to have some of the best vantage points in the ballpark.
I've sat in the Champions seats and the Legends seats and although those seats are padded and close to the field, section 227B will give you a good panoramic view of the entire field.
The only thing Yankee Stadium doesn't have that I wish it had was a view of the downtown New York skyline in the distance. Some ballparks incorporate the surrounding area much better than others.

What Yankee Stadium does have, however, is great food options. The Hard Rock Café outside of Gate 6 is awesome before the game. But you also have the option of buying something from one of the nearby deli's and bringing it into the ballpark. As long as you keep your food in a clear plastic bag, you can bring in any food you want.