I like the idea of the miniamp in conjunction with minidsp/minidigi however I think the output power is a little low, especially for EQ work which can use more power than usual.

Would minidsp/minidigi work with another digital power amp like the sumoh S60?

www.sumoh.com/

miniDIGI has a digital SPDIF output. Two output channels (e.g. left and right lows) can be routed to this digital output. Highs can then be used with miniAMP.
Routing depends on the used plugin, so you should take a closer look if this fits your needs (difference between 2.1 and 2way).

Ah great that was my next question.
The miniamp seems to be configurable as 2.1 or 2 way.
I have just ordered the minidigi, minidsp and miniamp kit.
I want to use it in a 2.1 setup with a separate active subwoofer (with its own 200W amp).
So I figure I configure the miniamp to two channel via SPDIF (L/R satellites) and the bass channel via the DAC.
I have also ordered the 2.1 advanced crossover plugin. I hope this is the right one!
I figure I'll work out how best to use it once I get it.
I can't really go wrong for the price.

2.1 advanced crossover plugin will work for you!

have fun!