Purdy Neat makes a great bag...just got my first one a month ago and love it.
I had a Travelpro before, and the morons at noservisair in Ireland broke the J-hook clip off (and to add insult to injury, threw the j-hook away). Not that it was hard to break....it was made with incredibly flimsy plastic. The bag itself held up ok though, but after carrying my flight case with me for a month, I coughed up the $300 for the Purdy Neat bag.
When I first started at a regional, I went to Walmart and bought their $30 rollaboard. What a mistake that was. At the time I shrugged my shoulders and thought "hey, it's $30...at that price, I don't even care if it lasts". Of course, I didn't consider the inconvenience and immense pain that would be caused to my shoulders after having to carry the bag for 4 days when the handle broke on day one of a 4 day trip.
The moral of the story...cheap bags WILL break (wheels, handle, zippers etc). And it will always happen right at the beginning of a multi day trip.