Full answer, yes. If you put say a tomtom one card in your rider it will think it is a tomtom one. I personally cloned the TT UK card onto a larger capacity card and installed extra maps to that.
The maps you have on your TT R1 card are activated to that product and will not work on the new units as the device ID is different.
You may be able to reregister the maps with the activation card if you still have it but most people loose it.
The maps on your TT R1 will be quite old now with many incorrect routes shown and they were the older Navteq maps which have less speed limit data and overall less resolution on the maps.
The new TeleAtlas maps are considerably better. Its around £70 for a new Europe map which gives you 4 lots of maps spread over a year and a new feature called MapShare which will keep you unit up to date for a futher year.
£70 = 2 years up to date mapping. Most customers wait 3 years between map updates so its likely to last you 5 years on total by my calendar.