I just installed a ZTW Mantis Series 35A ESC in my E-Cavalier.  It has a quirk that gave me a fright till I figured out what was going on.  After a test run the Cobra motor did not want to freewheel.  I felt like something had gone wrong with the motor.  I was about to remove the motor and unassailable it to find out what was binding.  I was interrupted and left the shop for a while.  When I came back the motor was OK. It freewheeled as it should.  I inserted an amp meter and did another test run.  Current was normal.  Turned the motor off and it was frozen up again.  I sat around scratching my head and flipping the prop.  The longer I waited the freer the motor became.   To make a long story short The ZTW ESC holds a charge for a long time after you disconnect the battery.  It is acting as an electronic brake. 

Outside of this non-problem the ZTW Mantis works well with my KR timer.  I bought the program card, $9.00.  It works great.  One feature of the ZTW Mantus, that I like, it has programmable reverse motor rotation.  I had all of the wires tied up and tucked away when I discovered that the rotation direction was wrong.  Took about a minute to fix.  This feature could also be useful to experiment between tractor and pusher props.  Anyway the ZTW Mantis looks like a good match for the KR Timer.