I ended up with two of these units, so one has to go.
RK2 with temp probe, ph probe, and the expansion socket for higher amp items. The only problem I have had with it is the backlighting went out so it is kind of hard to read during bright sunlight type times. Digital Aquatics said they could swap it out for $40, but I haven't gotten around to it. The unit is about a year and a half old.
$175
I will also sell the expansion socket seperately for $25 if someone wants it. If that happens the price for the RK2 will be $150, but the expansion socket has to sell first.