I'm currently looking for a fan controller also, though price is not such a limiting factor.

Taking a look at the aquaero manual p48 it states the load capacity per fan channel is 5W.

I'm busy trying to find out "normal" currents for different fans but I doubt you'll be able to put more than 1 or maybe 2 fans per channel if I've understood the manual correctly and if 3W is reasonable power consumption for a fan.

In comparison some of the mcubed options seem to support 20W per channel though I have no experience with them.

Hope this helps.