We have done both H&V and The Brown Derby.
My vote is for the Brown Derby. It is more expensive but the food and service were excellent.
H&V is a basic Disney Buffet (no characters since late 2002). The night we were there the service left a little to be desired (sode refills, removing used plates, etc.) Our best memory is that it shares restrooms with the 50s PT cafe.
We ate at HBD this APril for Fantasmic. We had Fillet Migons which were cooked exactly as we requested. The desserts were wonderful. Our server was very attentive. We sat in a small booth (there are 3 of us - DD is 8) - since it isn't a buffet there is not a constant flow of traffic aound you,