I think the problem is possibly the length of the zip needed to get around the offending area versus the length of the body.
I was told by a very nice man at Polar Bears that yes i could get a front loader, but to be honest the zip would need to be a longer one to get around my *ahem* ample chest and bum. This coupled with being a shortarse meant that the zip itself would begin a long way over my shoulder and end a good way around my hip. Putting it quite simply, im too short and fat for a front loader.
Hey ho, it could be worse....