The 3 SANSA e280's I've listened to all had great sound and the features like radio, voice recorder, and expanding memory were tops. But watch out for the so-called "refurbished" models' quality. I got 3 faultly refurbed ones in a row from Tigerdirect.com and was saved only by tiger's generous refund/replacement policy. The first one just went totally dead after a couple weeks. The second one worked fine EXCEPT for the microSD slot that couldn't read any cards (Used 3 2GB cards, tested good on other hardware.). The third one's display quit working in under 2 weeks. TigerDirect, incidentally, has otherwise always shipped me good-quality stuff and I recommend them.
The volume wheel worked just fine on working models. You can set it at high or regular via a menu, then use the volume knob on top of this. My only objection: the lowest possible volume was louder than I would choose for listening in bed.