I have had one on my Lauf True Grit for the past year, and you are correct - not much information out there. The Lauf has an Easton EC90SL crank with a 134 spindle. I called Quark, and several others, but the spindle length made it a challenge. In the end, I went with the Race Face version of the Cinch power meter, as it was in a 134mm spindle.

As far as the power meter itself is concern, it has been OK - not great, but not too terrible. For comparison, my indoor trainer is a Tacx Neo. According to DCRainmaker and GPLlama, the Neo is an accurate base for comparison, so when the Cinch was installed I did a few rides on the Neo and used DCRainmakers Data Comparator compare the Cinch to the Neo. Initially, the Cinch was WAY off from the Neo. Not 2%-5%, but different universe off. I made certain I was on the current firmware and did several calibrations, but it was still way off. I emailed Easton support several times, but they never responded (Easton is completely worthless at support, so just assume you will be on your own).

After watching a few GPLlama calibration videos for other power meters, I decided to dive in. I know Llama would have come up with a more scientific method, but... Essentially, rather than do a calibration with the left crank arm pointed down, I rotated the arm to 9:00 and did another calibration. After comparing a few rides on the Data Comparator, the Cinch was getting closer to the Neo. I then applied a little pressure to the crank arm during calibration, and eventually got the Cinch to measure very close the Neo. From 150-200 watts, they are usually very close - within a watt. However, at 250 watts (my current FTP), the Cinch measures about 10 watts lower, and the higher you go, the bigger the difference. While this sucks, I know it and make mental corrections above 200. When I do structured workouts on the road, with intervals at or above FTP, I know I need to aim higher. However, for endurance sessions, or longer races the 150-200 range is fine. (Note: I could have done the calibration so that the Cinch and the Neo were closer at 250-300 watts, but I am happier with it at 150-200)

Aside from that... it has worked well. Reliable and no dropouts. And, yes, I would rather have a more accurate power meter, but the Cinch was the only power meter that worked with my bike at the time.

Also, you may want to look at the Power2MAX NG for Easton/Race Face, as that may work better.

Good Luck!