http://www.forum.digitalaquatics.com/
The $99 package is great for controlling lights and fans. (that is what I have it for) Since you are limited to only 4 plugs if you are wanting to control more you will want to go up to the $279 package or the elite. I think if you trade up they give you a $125 credit towards the elite? Which I only paid $99 for the RKL with one module and 1 temp probe