Cyclingnews Verdict With longer battery life, broader detection range and FOV, and finally USB-C charging, the Varia RearVue 820 is a huge upgrade on the previous RTL515. Many new features have also been added, but all of these updates do come with an equally updated and boosted price. Pros + Best detection range of any radar tested + Wide FOV for detection + Huge array of mount adjustments + Long battery life + Customisable modes Cons - This is now the most expensive standalone rear radar light - Many of the features are limited to Garmin head units - Battery drains quickly with additional features running - Bluetooth connection was at times patchy You can trust Cyclingnews Our experts spend countless hours testing cycling tech and will always share honest, unbiased advice to help you choose. Find out more about how we test.…