I've got the model that's the biggest of the two in the link above - is that first generation? Anyway I've found it reliable, although a little susceptible to shadowing. Btw when in tracking mode you don't need to keep pressing "OK", it automatically updates your position every 20 mins (although I find this varies quite a bit) for 24 hrs, then you have to reactivate the feature.
$120 a year (and that's US, which makes it even cheaper in Aus) is chump change for this service. |