Not completely on topic because I can't recommend a specific wheelie, but the thing that has annoyed me the most with the wheelie and duffles I've owned is the p!ss poor quality of the zips used. Each time it has been zip failure that's meant I've had to get a new bag. Which is a shame, as my Kookaburra pro duffle was excellent apart from that.
If there is a brand out there that can specify in their design, or manufacture, good quality zips (e.g. YKK) then you will have me as a customer.
I take my kit to games on the back of a motorbike, so working zips are important. As a biker, I've also found out about quality zip makers and why it's worth paying a bit more for them because zips are everywhere on clothing.