Land rover watch gps tracker

Hi, did a quick search to see if it'd been mentioned before and couldn't find anything... I believe it's fitted standard to new range rovers etc, but came across one cheap and wondered if it could be fitted to my 1985 90? That said, can you run it without a subscription? If anyone's got experience of one I'd love to hear a review...

Some info over ere: https://secure.eurowatchcentral.com/landrover/article.aspx?rno=178#Background