I had my first ride with the Varia connected to my Edge 520 this weekend.
Initial pairing of Varia with Edge 520 had gone smoothly a couple of days earlier and there were no problems when reconnecting before setting off. I selected the course I was going to follow and rode to the start point to join the other riders. After about 5 minutes we were ready to go so I pressed the start button on the Edge 520 and set off on the course. The Edge 520 found the previously set known elevation point for the start location and then threw a 2:1 error indicating that the Varia and Edge 520 had had a communications disagreement and lost contact with each other. The Edge 520 appeared frozen at this point with no map updates as I cycled slowly along trying the Return, Enter and Menu navigation buttons - all with no effect. In classic IT support mode, I turned the Edge 520 off and on again, the route instantly can back to life, all sensors connected and nothing missed a beat for the rest of the three hours I was out.
The Varia notifications worked exactly as I expected based on the descriptions provided by Garmin. The issue of cars holding station behind the group of riders (12 of us in this case) worked better than many have indicated. A vehicle approaching the group is identified, as it slows to match the group speed the indicator dot disappears and the green bars are displayed indicating that the vehicle is no longer coming by. Then, when the vehicle decides to come by, the change in relative speed is noticed and the amber bars and vehicle dot come back on the display. This worked in most situations except when the vehicle came past the group very slowly with little difference in speed compared to the group, but in all cases I knew that there was a vehicle there because the Varia had previously alerted me and I'd had a quick check over my shoulder.
On straight and gently turning roads I knew there was a vehicle approaching a long time before I could hear it and this on damp roads with the additional tyre noise that creates too. On more twisty country lanes, most of the time I was aware of the vehicle from its noise before the Varia alerted me, but it did always alert me, once the Varia could see the vehicle.
The Varia was not so good at detecting multiple tailgating vehicles running completely line a stern. This is something that Garmin makes you aware of in their literature. As each vehicle passed, it was immediately replaced with another on the display, so they were not missed entirely, just you could not tell in advance how many vehicles there were, but you did know that there was something that was coming by.
I didn't test the audio notifications in this group ride, as with the Edge 520 (and other newer EDGE units as far as I know) there is no granularity over the sound controls beyond all on or all off. Riding with a frequently chirping Garmin in a group is a real no-no, so I'll try this out when riding on my own. Garmin really need to add better sound control selection, the Edge 500 had some granularity in this area, so this is another backwards step with the newer Edge models.
I didn't notice any massive battery drain on the Varia, just one light had gone out after three hours of use. Adding the Varia to the Edge 520 connections I use for all rides (GSC-10 (on this bike), heart rate monitor and Bluetooth to a Nexus 5 running Android 6 with call notification only) added no significantly large additional battery drain.
The Varia system provides another "sense" that, when used in combination with the traditional ears and eyes, definitely adds to ride safety but should not be relied upon solely without those additional checks - you'd always make those checks anyway wouldn't you?
Apart from the initial communications error, I was very pleased with how the Varia worked in practice in a group ride. Is it really needed? No. Does it add a little extra safety? Yes. Will I continue to use it? Yes.
