Stay away from telenav. There are too many bugs with the program and the 8700. When something goes wrong they always blame it on someone else.
But, if you are ok with problems, the program is great when it works. There is another option called Wayfinder.
www.wayfinder.com. The program is a little difficult to navigate through the menus, but the functionality and stability is better than Telenav.
After 2 years with Telenav I was forced to buy a dedicated GPS. Having to pull over on the interstate the wait for the BB to reboot (caused by Telenav) several times was enough. Goto their website and read the forums and you will see that they are giving all 8700 users free service because of the problems.