I have used the Pepwave for a couple years now. Works great at creating my own network from the relatively weak CG wifi signal.
When we are not on the road, I use it at home as a 'Repeater' (with a different SSID) at the opposite end of the house from my router. When I bought the Pepwave, I also bought the external antenna they sell with it as a package. I have found that the while the external antenna works, it does not improve performance enough to justify it's additional cost. Or maybe I have not been to a location where the CG signal is weak enough for the external antenna to make a difference.
When you set it up to use in the CG, create your own SSID (I use 'ontheroad') and be sure to have a password for access to the Pepwave network. If you don't, you will have everybody else near you connecting to your Pepwave network and slowing you down.