The story goes that the Army actually prefers larger Fijians for their rugby team, and I don't doubt for a second that they're at least the equal of the Gurkhas as individuals; see the accounts of Sergeant Labalaba at Mirbat for just one example; IMHO he should have gotten the VC for what he did. And the Gurkhas do indeed consider picking fights with their Fijian counterparts to be great sport, as they do engaging in little affrays and sporting tiffs with those of the SAS Regiment. The Gurkhas have some peculiar ideas about recreation, but they're certainly game and sporting about it.
But you can see a transcript of some of the Parliamentary discussion on the subject on the subject *here*.