[otherguy]

Any consensus on whether or not this is legal for FRC 2017?

I could see them being legal if they were considered to be a servo.
I guess my holdup is that when I think servo, I'm picturing a rotary RC hobby type servo (Futaba/HiTec)

They don't look like a traditional servo, but electrically they are effectively equivalent (A DC motor w/ built in potentiometer for feedback). And the rules do not specify that a servo should be rotary/linear. The manufacturer of these components (actuonix) sells them as linear servos.
The only real constraint on servos in the rules appear to be cost (<$75) and they meet that. They also don't draw more than 2.2A in stall, so no immediate concerns about brownout. I think I've convinced myself they are a servo... I'm just not sure every inspector would see it the same way. Thoughts?