I have NAV TV in my 2014 Raptor - I like it and found it to be worth the cost, as I use the front camera all the time. I leave my computer in the setting that allows me to simply push "OK" on the steering wheel and the front camera is immediately activated.
I thought I would use the NAV anti blocker feature more than I actually do, but when driving it is nice to have the option to work with the NAV without access. However when you use this feature and put in the address you want to go to, it will accept show that you that the destination setting, but the map on the screen simply freezes on the spot you are at, until you turn the feature off (but the verbal directions will commence as normal). Once you turn the anti blocker off the map on the NAV immediately goes to working as intended.
Sometimes when you hit the camera it will have a wave in the screen and have to roll thru the screen to give you the full picture.
May be Nav TV issues or install issues - but these are things that have popped up over the past year as I used the system.
This is one of the upgrades I have used on my truck and I find beneficial on a daily basis.