I bought the nicer one. As a WiFi hotspot, the only difference I see in the specs is that the nicer one supports up to 15 devices and the cheaper one somewhat fewer.
The nicer one has a bigger battery and a USB C port. The implications of the USB C port are that it can charge that way, but it can also serve as a power bank to charge your phone. You can also connect it up to a laptop and tether without WiFi, or hook up a mass storage device and serve the data on it out over the WiFi connection. I'm not sure how many (if any) of these activities the cheaper one allows.
All Jetpacks are relatively the same in regards to thier primary function and niche market. Minor differences between the models boil down to features like external antenna options, USB ports, USB modem, admin features and whatnot.
Most people get into trouble with Jetpacks when they inaccurately assume that they can be used as a 24/7 home internet replacement device. They do a poor job at that role and VZW has devices that are better suited for that situation. As long as all you need is temporary mobile hotspot access and use the device within its intended design parameters you should be fine.