COTS Shifter Comparison Question

[TheHolyHades1]

Hello.

We've been looking into the various COTS shifter options available and we've come to find a few different options so far:

AM Supershifter: http://www.andymark.com/product-p/am-superoptions.htm
AM Sonicshifter: http://www.andymark.com/product-p/am-sonicoptions.htm
VexPRO 2 CIM Ball shifter: http://www.vexrobotics.com/ball-shifter.html
VexPRO 3 CIM Ball shifter: http://www.vexrobotics.com/3cimballshifter.html
WCP DS Gearbox: http://www.vexrobotics.com/wcp-ds.html
WCP 3 CIM Dog Shifter: http://www.wcproducts.net/wcp-shifter-3cim/

And we have a few questions.

1. Does anyone know if more COTS solutions exist? It seems each of the major FRC parts suppliers has their own, and I think we've covered all of the major suppliers.
2. How do the gearboxes compare to each other in terms of durability, ease of use, ease to modify/change gear ratio and motors, shift ability, shift speed, ease to mount, etc? We're a relatively low budget team and currently don't have the budget to do testing with all of the various designs.
3. Which one would you recommend (doesn't have to be from the list)?
3. Overall opinion on shifters?

Thanks,
Hades