I installed the VECTOR from trail tech with much success. This weekend I rode with a group from MVTR (in NH) that were setting up an enduro course, and the vector was tracking with everyone else's mileage. I got the handlebar switch for an extra 18 bucks that lets you reset the trip odo to a specific mileage, so you can follow roll charts for an enduro/turkey run type event. BTW, it rained on us for 6 hours so I can attest that the vector can take quite a beating.
Of note: I did not install any of the "fancier" features of the vector, like coolant temp, tachometer, etc. I merely wanted a correct tripmeter, odometer, and speedometer from changing the gearing and tires.
Installation was easy; one of the two magnet-topped rotor bolts that comes with the kit fits our bike perfectly... I used blue threadlocker just to be safe. The pickup mounts to the caliper, on the outside of the caliper but still inside of the caliper mounting bracket attached to the fork, so it's real cozy and safe in there. I made an aluminum bracket that bolts to the handlebar risers (using the template that comes with the kit) in about 30min... more robust than the stock plastic handlebar mount, which IMO is the only thing this kit falls short on.
Pictures to follow once I get some and figure out how to post them.
Ride safe,
Shawn