Never buy a new model running NC10 like the VIA if you are not willing to pay for maps or want more than what the NC offers.
Suggesting to buy such a device to a forum member is not nice
Best price option is the 720 or 730, 520 and 530 are a bit hard to get these days.
The 720/730 offers all hardware features a user can need (apart from Live what needs a connection from your phone) and it is easy to modify.
Keep a good working NC on the internal memory to play with new stuff on the SD, if you are in trouble on the road, revove SD and keep going
Also: they are fully compatible with the truck map and Navcore.