I have a spec, have had it running for almost a year (I think?). I had to upgrade the light also. The stock LEDs are not sufficient for reefs. I went with a clamp on pc, so I can only keep low light stuff in it.
I've got a kenya, a couple mushrooms, and some "trash" palys doing well in there. There's a handful of dwarf ceriths, a tiny nerite, and a limpet. Some collonista snails went nuts breeding so they take care of the glass pretty well.
I would never put a fish in it, it's not nearly big enough. I even took out the hermit crab I tried in there, I just felt sorry for him.
I change half a gallon every week, but have to top off every other day. A lot of evaporation on a small volume of water can be troublesome if I don't stay on top of it.
I added an extra little filter for more flow. Might not be necessary, but the kenya looks cool swaying in the current. I had a JBJ mini filter with a spray bar available, it fits nicely in the back chamber. I gutted the filter area and filled it with rubble. I show a carbon pack in there, too.
Also, I don't think it actually holds 2 gallons, more like 1.5.