I personally love our West Coast Products 3cim dog shifting transmission.
Was a wonderful addition to our drivetrain and was the sole reason our robot was such a great defensive threat during Arial Assist. We were the assaulting robot for the first time for our program and it was a nice change.
We do not have the PTO option but are considering it for this year.
Since we went ahead and bought a bit more transmission than we really needed for that year (3cim versus 2cim) we have the ability to add it easily.
I have run the transmission in 2 and 3 CIM configuration with no issues.
As mentioned, having a transmission module easily swappable can make or break a season. Plus you can easily modify gear ratios to get the perfect speeds / torque you require during prototyping.
We will be using them again this year and will be looking forward to doing some serious breaching!
Any question feel free to message me and I can video or Cads of our robot with the WCP WCD 3CIM transmission setup.
Good luck with this, and the season ahead.
Aloha!