I would go 72'' high before 102'' wide. We have both widths of hoppers and the 96'' wide trailers will consistently pull .3-.4 mpg easier. We also notice odd tire wear patterns on the outside tires on the 102'' trailers.

PS: don't get ag hoppers if you are going to be hauling bulk commodities unless you want a lot of exercise!

   And if you must have a 102 X 72,,,,,,,, here's a nice one.

http://www.truckpaper.com/listings/detail.aspx?OHID=1976422&guid=485BDB0F18B94D669D3F256D80AFA4ED