We are using a Verizon 4G LTE VL600 modem in a warehouse attached via USB cable to a Win 7 desktop. The service varies 3G to 4G but often losing signal when we need to check mail automatically, unattended. The VL600 was initially chosen as a test of concept for that location and the fact we could use it on a laptop elsewhere. Since we are committed to that location we need to upgrade to a better modem for a continuous connection for checking email every 5 minutes. (low traffic). Any suggestions for a Verizon modem that would be a better fit?