Hi. I currently have an old Garmin Streetpilot which I have had for years and I'm thinking, finally, of upgrading. In my BMW it's fine but I also have a Jaguar XK8 convertible which has a heated front screen. I need to use an external antenna with my unit or it loses satellite signal.
The new Garmin units don't have the option of an external antenna and Garmin have not been helpful.
Does anyone know if the newer units are more sensitive are likely to be OK or do I need to look elsewhere?

I would just carry on with my old unit but it is on it's last legs in that the battery lasts 20 seconds and there is a small defect on the screen now.

Any advice please?

Many Thanks