I like these for the ability to put on my track bike easily vs buying a new crankset.
I don't like that the pairing seems to forget itself (garmin-to-garmin) if my computer moves anywhere away from the bike then comes back. This could be a "me" problem, but I keep my computer in my jersey pocket for track racing, since they're not allowed to be visible while riding. If I walk away from my bike between races, i have to re-pair the sensor, by rotating the cranks backwards, which is pretty frustrating.
I've got a stages on another bike, which works well and pairs better with my head-unit (even as a non-garmin product). Just didn't want to buy a track crank and have to retrofit with a stages PM for a single bike use.
an important training tool
accurate, durable and reasonable in price
With a 15MM pedal wrench it's a quick change from outside to indoors. Completely compatible with all computers it's a snap to go back and forth. Less changing and more good numbers to motivate and stats to read deep into working hard or keeping from working too hard. Great product