RECCO

It's simply a reflector that specialized detectors can pick up and locate similar to beacons. Ski resorts and some S&R have the locators.

It is essentially a passive one way (transmit only) beacon that can be located with special equipment. They're very common in high end outerwear now, and won't effect your beacon or anything else. They're designed in case of Avalanche in bounds or in the side country of a ski area where most people won't have beacons. A good backup to have, but that's about it.

It is a tool for organized rescue, not companion rescue. It won't interfere with companion rescue, but it won't help it either.

If you ride someplace with reliable cell service, and very quick organized rescue (SAR) response times, then it could be factored into gear buying choices.

But if you ride where cell service is unreliable and/or SAR response times aren't very quick, then RECCO is probably nothing more than a body recovery device, which your beacon will already handle unless your body was buried so long that the batteries died. In that case a dog might find you.

I think in general it's a good thing to have but not a major factor to consider when purchasing gear with the intent of using it in North America.

I've been on a handful of SAR searches where the missing person was reported to have gear on supporting RECCO. Not once did the system prove useful in my experience(some of them did not have RECCO) but there are reports of varying levels of success. The receivers have gotten better smaller over the years with the newest handheld devices including a 457kHz receiver included. One thing they are good at is finding soda/beer cans and lift ticket hangers.