I picked up a 7x22 3 place inline this year and almost always have loaded from the front to the back, actually only loaded rear to front when I had 2 sleds in it. If you have room to go either direction you'll be influenced more by things like, how much room you have when loading for the front ramp to drop down, if front or rear facing gets you more room by the side door to throw your gear, if you have a little better weight distribution one way or the other but probably it will just be whatever habit you get into. I think you have a little more room for things to fit front to rear. For me the tail of the third sled fits nicely into the V and still gives me room for gear, not sure I'd have as much room if I went the other direction.