To be honest, if you are running at 24v and only drawing around 20amps then I would look at a ragebridge 2. You can pick them up from ellis at ranglebox or straight from the source at equals zero designs and order them from the US. They are dual channel controllers but can be run as a single channel controller. For the same price of the roboteq you could have 2 of them running single channel or a primary and a spare with a bit of change left over!