I just bought a 2015 Model S and unfortunately it only has 3G connectivity. I have been strongly considering upgrading to LTE, but it looks like that's about a $600 upgrade. Tonight I happened to see the ZTE Mobley hotspot on AT&T's website and it looks like I could get one of those and add it to my existing plan for only $10/month. If I connect the car to that then essentially I'll have upgraded the car to LTE and at $10/month it would be 60 months before the break even point. And quite frankly, I suspect that I'll have sold this car and upgraded to an AP2 car before 60 months. The hotspot has other advantages too, such as a connectivity for a cloud enabled dashcam. Is there anything I'm missing here? Any strong advantages one way or the other? I'm not too worried about data usage of the car... my plan has 30G of shared data and I don't think we've ever gone over 20G. I don't see the car using anywhere near 10G a month.