ok, well I did say it was a dumb question.
thanks anyway.
I've updated it to 2004 map and TMC anyway, and updated firmware to latest it can go to, so get split screen and stuff. It's a damn site better than it was.
I notice map direction is a bit weird.. it only lets you set map to direction of travel <900 yards zoom as far as I can tell, above that it's north only which is a bit crappy, but then again the thing was designed in the 90s at the end of the day, so it's hardly a surprise that tomtom running on my phone is better in every way. beggers can't be choosers I suppose.
stu