Well, yes - any wireless connection can be unreliable when you're at the limits, whether it's FM, HAM, CELL or WIFI...
When I got mine it was only $15/mo IIRC. Even at that I didn't feel it was worth it. But that's in my circumstances. The most valuable part of the package (to me) is the remote start ability. However,
my truck is parked in a "heated" (40°) garage at night, and it's within remote start distance of my office during the day. Once in a while I'd use it, say if we were at an event or something, but it just didn't seem like I was getting my money's worth. $15/mo doesn't sound like much, but over 5 years it's nearly $1000...