I'll defer to many who know more than me, but...
I'm under the impression that scanning coins is the "Plan B" if you can't get a decent camera. There are many, many threads about optimizing your camera to take pictures of coins. The threads about scanning coins seem to say "in spite of the fact that these are scanned, they turned out OK!"
If you bought the scanner for the sole purpose of coin pics, I would return it. Even if you have a poor camera, you could invest in a tripod and some type of lighting to optimize your pics.
This is my opinion because I recently scanned my entire coin collection. The images suffice for archival/insurance purposes, but they aren't 'high quality' enough to show off to friends or potential buyers. If your goal is to quickly document your collection, a scanner is OK. If your goal is to get high quality images to help your selling, you may want to focus more on camera pictures.
just my humble opinion
-wheatiefan