I don't like any of those AquaC skimmers for several reasons.
First they are ridiculously expensive for 25 year old technology.
They do not come equipped with a pump so expect to pay another $100-200 for a quality pump.
They are not needle wheel skimmers, which in today's age of energy conservation is pointless. Needle wheel skimmers are worth the money. Not only do they skim circles around injection or forced skimmers, but they save electricity, don't generate as much heat, take up less space.
Everyone I've ever known that owned a large Aqua C hated it. They hav a tendency to suddenly go haywire and overflow all over the place. This has happened to several people I know in person and online. A friend bought a used tank that came with a large Aqua C unit and it has not produced any foam for him in 3 weeks. The standard answer over at Aqua C, wait for it to break in..