I am looking for a bag that is similar to the Tumi Alpha FXT Wheeled Compact Computer brief but that costs slightly less money

http://www1.macys.com/catalog/produc...xx.esn_results

Specifically, I am looking for a bag that has wheels and also has a shoulder strap. I also would like the bag to have the back pocket that allows it to slip over the handle of a wheeled carry on bag. I would like to find a bag for less than $250 or so. If you know of any bags that have these features, I would appreciate your input. Thanks!