Well... I've had an established 10g BB nano running for about 2 months now, it was/is a friends tank
as for maintaining the tank for the last 2 months, I've had no major issues to speak of.. I am new to salt but I have kept african cichlids almost exclusively for the past 9-10 years.. Since this neat little salt tank was transplanted into my livingroom, already containing 6x 6 foot cichlid tanks and a 72g as well, not to mention one of the bedrooms... The little tank started to grow on me and the maintenance was not all that much for a tank of this size. I started to get a little curious of how difficult it would be to get one going... The tank & filters were just sitting around, so I set it up.. It's a 10g with 2x hob filters, live rock in one HOB, Caulerpain and small bag of aragonite in the other (all from a friends established tank) 15lbs LR from that same established tank, and water from the same tank, I have a single clown fish and a single pom pom crab, a few very small things on the LR besides a bit of coraline algae..
I like the idea of sand as far as asthetics are concerned, plus the extra critters in the sandbed. Still thinking....