I have had it running in my sump for a year without too many major issues.
It is relatively quiet, and does fine in pulling out gunk from the 57g Illuminata with a 15g sump. No microbubbles return to the display, I empty out the cup every other week and clean it, pump has started and stopped fine every time I've plugged it in/unplugged it. I recall that it was very reasonably priced too.
The issues I have had are:
The mesh prop can crack or break leading to a loud knocking sound from the pump (they give you an extra one in the box).
No way to adjust air intake rate - water volume is adjusted by a wedge pipe.
I will get salt build up near the top of the skimmer body where it begins to taper toward the cup. The acrylic joint isn't perfectly sealed, though it isn't a major leak.
I have had something block the outlet (snail, debris) leading the skimmer cup to overflow. This has happened maybe twice or three times this last year.
I'm out in the Outer Sunset if you ever want to swing by to check it out.
The only previous experiences I have had with skimmers were the Aqua C Remora and a CPR BakPak on a smaller (20g) tank, so I can't really do a real comparison.