To be honest my concern with trackers are the 'black box' ones offered by some insurers, that determine your driving safety by looking at speed, braking and acceleration style, time of day, etc. It's not that I'm a bad driver by any stretch - I'm certainly better than the majority of idiots I encounter on the roads of south London - but I don't think I'd want to share my not-irresponsible exceeding of the speed limit (such as on clear motorways in good conditions) with an insurance company because they'd naturally take a very dim view of such activities. To be honest being a male driver under 25 in south London, I've already paid the price through insurance for my age group's misdemeanours on the road, and I don't want to give them any reason to believe I'm part of the same group of irresponsible drivers.
I've worded this carefully so as to not start an off topic argument about speeding, but tldr: I'd only consider a location tracker, not one that can/does track speeds/g forces/etc.
