I will say that the unit I was useing was a pre production unit but I understood it was as the production unit was going to be. That being said it was about 9 weeks till they realy released the Max to the public. I have 6 Maxes inhouse and have not tried them on 5s because of the past. The ones I have are the mose recent release so there may be a diferance. I will be on the phone today conferming upgrades to the units. They run 4s great but I do not like to start fires so I have not been willing to destroy another $1500 car. I cannot release all information because of non-disclosure agreements but I can say the it was an 1/8 scale conversion on an Serpent Vector 2wd. The motor was a Neu 1509/1D. The batteries were Max Amps 4000 cells. The thing ran for about 30 seconds befor I noticed a problem and I ripped off the body. Litterally ripped it off. I looked at the controller and it was smoking all wires looked good. I wanted to unplug and turn it off. I flipped the switch and the thing went balistic. It then crashed into a concrete wall at at least 60. This wall was about 50 feet from where I was. Everything burst into about 10,000 peices. The battery did not fail and I still use it today and the control was a melted nightmare. Now I had been running the set up with 4 cell and 3 cells for about 2 hours and it was great. The only change was the 5 cell. Even when the the control was smokeing it was not hot to the touch so I know it was not over amperage. The data logger never worked after that again. The Quark might be the better choice if you continue to use the outrunner. It has multipole programming in it already. THe Max and the BK donot. THe Max will have it soon as an downloaded upgrade.