I bought this wheeled duffel for its smaller size than other carry-on wheeled bags.  I've used this on one trip so far and love it!  It easily fits in a plane overhead (have not tried it in the expanded mode).  The retractable handle is smooth to operate and more than long enough for a tall person.  I love the divider option in the main compartment.  Although I use the eBags packing cubes, the divider is great for keeping items from shifting too much.  I also like that the main compartment can be accessed from the front large zippered opening if desired.  I kept my travel liquids there, ready to pull out during airport security.  The bottom is sturdy hard contruction and the remaining fabric is heavy duty.  The compression straps on the sides are great for cinching down the packed duffel.
This duffel is exactly what I hoped for!  I plan to replace my larger suitcase with the 25" wheeled bag as well.