Hey,
I was at little river yesterday and there was a guy with a bullpup 300 win mag with muzzle brake. Short barrel too.
He was packing up so I didn't want to be a pain and ask for a shot too late, but the questions is - between having the shorter barrel and bullpup config the brake was a foot (or more) closer to your face than it might be on a regular rifle.
I've stood behind/side of brakes before and you get buffeted around a bit.
On the bullpup, are you not copping your own muzzle blast coming back on you all the time?