OP, don't think you can go wrong with any of these brands. We were looking at all of these in 25-28 ft. bumper-pull versions over the last two months. IOO (in our opinion), the Genesis Supreme and Eclipse had a slightly better fit and finish than their competitors.
Aluminum siding is less expensive upfront, easy to dent, harder to clean, and cheaper/easier to repair. Smooth fiberglass siding is easier to polish/clean, more dent resistant, more expensive upfront, and more expensive to repair. Choose your poison.
In the end we decided to pass on the bumper-pulls and went with a small 32 ft. 5th wheel toy hauler for about $10k more.