Yep... Cp3 over cp4 is the common. Cp3 does not need to be timesd. We just tuned a Lml with a exergy 12mm cp3, very nice setup but required a little tuning to make it "happy".
Things have come a long ways it's just nuts, I think one of the coolest things is controlling the dual pump setup without a controller.... Controllers deff still have their place, but I foresee everyone going without controllers in the near future. Everything just "works".