Skriz;432107 wrote: The RKL is not compatible with the SL2, so you'll have to get an SL1. You'll also have to add the ph probe and another PC4. When you do this, you're at $295.
The ACJR with a DC8, ph probe and temp probe is $257. This is the best value in controllers.
The RKL $99 base price is a gimick that'll naill you in the end.