In reply to James Gordon:
If you want all the info including from independents such as Manuel Genswein just go here
http://beaconreviews.com/transceivers/
The point has already been made that Tracker 3 is not yet available despite many promises, the same was true of Tracker2 but in fairness when it arrived it was very good.
It's a bit of catch and mouse - the Pulse (3antennae) was available before the Tracker3 so I got it but I now find the T3 is simpler to use.
I reckon that what you want is to have the one that works for you with the lightest shovel and probe but above all you want your companions to have the biggest shovels, longest probes and the transceiver that really works for them thus I give them a Tracker 2 and have a Pulse myself!
However the conclusion is not what transceiver but how much practice.
I believe the fastest time ever achieved in a Guides test was by some one who used an analogue Pieps with earphone.
He had practiced a lot. Even today, I understand the record stands.
Tracker 2 with lots of practice.