Trailer Width
I have a 7.5 x 24 plus the 5' nose. Pulls nice and I can see around it with my stock suburban mirrors for running around in MN. When I go out west I add extensions to the mirrors.
Don't underestimate the space give up for the inside fenders, especially on a triple axle. I'm not saying that the width on either side of the fenders isn't beneficail, just that the middle works better for tunnels and both ends work great for skiis. I haven't at all had to resort to backing any sleds in for winter transport. I do it for summer to hold 5 sleds easily my having skiis to tunnel on the sleds that are next to each other. As I ease out of trailing arm sleds I think it will get much better.