I use the Varia Tail Light/Radar on both my road and gravel bikes. I set up mounts specific to each bikes seat post. The O ring straps only last for a limited length of time before they break so attaching a tether from the device to the seat post provides extra security. A tether should be included in each package. The rubber adapter pieces that nest together are easily lost when changing bikes. Spray adhesive can be used to keep these pieces together.
Although I own a Wahoo cycling computer, I opted for the Garmin sensors since they are slightly more affordable than the Wahoo equivalents, but also because they flawlessly integrate with the head unit.
I have two bikes using Wahoo sensors and although they get paired quickly, one of the speed sensors eats up batteries like crazy. Also my Wahoo HRM just doesn�t want to pair with the head unit - it takes way too long and requires shutting down the Bluetooth on my phone before attempting to pair.
The Garmin sensors however have no issues - my Varia RCT715 (radar camera taillight) pairs immediately, and I do mean immediately, regardless of whatever order I start pair sensors so I decided to try the Garmin sensors. I�m glad I did because they have performed excellent.
This mount works well and I really appreciate the Gopro mount on the bottom. It's a bit on the long side but works well enough and adjustability regarding display angle is adequate. While this mount is listed as for Service Course SL stems, the finish is that of just the Service Course line. This means it doesn't match the finish of a Service Course SL stem which is a matte dark grey finish as opposed to the semi-gloss black of the Service Course line.
Solid product - very clean looking design and I've done probably 600 miles since install and haven't had to adjust or mess with it once. Install was a little fussy, it took some fiddling around with angles to get the bolt started, which makes me nervous when dealing with a $300 stem. The adjustment range is fairly limited, though if you're this far down the dollars-per-watt curve then you should be willing to make sacrifices.
2 stars for price, I don't care if it's my punishment for running an Enve bar/stem, it is ridiculous for 2 pieces of CNC metal and some fiddly bits.