Couple of other points to consider, you can buy an RDS Receiver for virtually any TT for Traffic service but I don't think it's as efficient as the SIM card based version which the x40/x50's use
You can also clone/piggy-back Live services from one subscribed (x40/x50) device to any other x40 or x50 device. I have a 940 running Live Services cloned from my subscribed 550