I have this one
http://trackmefree.com/viewitem.php?productid=2 in my Evoque, it just sticks on with magnetic back, I have put it behind the pull out on the left side of the boot, it does not have a full view of the sky but works perfectly well and the best thing is it does not need any wiring just charge it up and stick it on. it is supposed to last 60 days between charges, I have had it in 2 weeks and it still shows 68% charge so maybe it will. Downside is it is not insurance company approved but at less then £200 with no subscription fees I think it is well worth it for the peace of mind.