Dunno if you've created your tank yet, but here's my two cents: When I had sand in my 12 gallon, I found it annoying. I had a strong filter on the tank, and so within a day there would be a "hole" in the sand where the filtered water came into the tank.
Other than that annoyance, it looked lovely and I really liked it. I probably should have just put a baffle on the filter (something I didn't know about until years later).