Recco is the best technology we've come up with yet for body recovery in the mountains. It doesn't run out of batteries, so they will find you eventually.
Seriously though, by the time ski patrol gets to the slide, gets their recco detector working and digs you out, you're dead.
The actual recco system is basically an RFID tag or something along those lines embedded into your coat. You hit it with the right frequency, and you get a return signal. Normal beacons will not find them (as far as I know).
No beacons detect recco except for the one specifically made to find recco detectors in coats.