If you're running a herbie setup, I would recommend spending the additional on the DCP pumps. The fine adjustability on them makes tuning the herbie very easy. I don't even have a trickle in my emergency drain because I can back down or bump up my pumps so slightly that I can get the water line to just under my emergency drain.
I like my DCP pumps very much. At this point, I can't say enough good things about them. They are completely silent and really move a lot of water for their power usage.
jvc66
Being able to change the settings in smaller increments is a moot point. The gate valve is what needs to be tuned. So again just go for whats cheaper dcp sounds like a great pump but so is the dct and im sure the dcs is just as good. Imo wether there are 10 speed setting or 100 they are both going to be in the ball park and i could see not even using the smaller increments....example :
Pump is running at 1000gph you tune your gate valve, achieving silent siphon how is adjusting the pump to 1010, 1020 ir 1030 gph going to help ? It isnt. Especially since you plan on joining the drains into 1 gate.
Get either of them as long as it can be adjusted your fine since the small adjustments are being done at the gate valve anyway.
Dct is silent, dcp is silent, im sure dcs is quiet but maybe find someone who uses them to chime in or comment