I you're not going to buy a 9900bx or a trafficwatch, I think it's still worth getting the gtx330.
If nothing else, it will convince you to buy the 9900bx or the traffic watch.
but in the meantime, think of it as a subscription agreement.   If you pay an extra $2000 and
only use it for 3 years that's $50/month for coverage in most busy areas in the US.   still worth it IMO.

Colyn