Sierra Wireless AirLink Raven RV50
This is a great in-car modem if you want terrific performance with low power requirements, but the lack of wireless connectivity can be an issue. However, performance is definitely not an issue with this model thanks to support for 4G LTE networks. One unique feature with this in-car modem is it's designed to run on a very low amount of power, requiring the same amount of power as a modem with 2G support, while offering 4G performance. The low power requirements mean you don't get get any wireless connectivity, but this model has an Ethernet port and a USB 2.0 connection to make up for it. It conforms to military standards for vibration and shock protection, so this is a great choice for a vehicle expecting frequent travel through rough terrain.