IMO Brown malt is sort of a misnomer in that it makes you instantly think of a brown ale, but I feel it needs to be used with restraint.
I used a 3/4# of it in a mild recipe. I was almost unexpectedly, too much, it gave the final product a really heavy nutty flavor almost hazelnut coffee-ish flavor. I didn't mind the flavor but I was really going for a mild background flavor. It was more pronounced in nut flavor than a Goose Island HexNut or Rogue Hazelnut Brown.
It was only 9.25% of the grain bill, So I would suggest caution in using it in large ammounts unless you were going for a really nutty flavor.