If you are running the truck hard you will notice the loss of power. If you are not running hard it can creep up on you. I can usually tell before I hit the lvc, but I still set it anyway. Plus I set it for 3.2v per cell for a little "cushion" in case one cell discharges faster than the others.
I still run mine on 5S but won't be able too on 6S. I'll set the lvc at 16v and see what that does tonight. If it hits before I notice power loss then I'll get a lvc of some sort if I notice power dropping before then I won't mess with it. All in all for the most part I don't even run my truck for that long. I got around 37min last night of very hard running on open asphalt with a 4000mah bat.