Hello Scott - I have a Prime and love it. As long as you're charged, driving in EV mode on the freeway is a snap. Actually, in "Normal" mode it will automatically select EV or HV for you, depending on your charge level. The West Coast dealerships I contacted were charging $15k over MSRP. I did a google search and found a dealership near Boston that sold one to me for MSRP (hard to believe I felt I'd done a great deal by "only" paying full price). I considered flying to Boston and driving it home, but decided to have it shipped instead. Putting the deal together was time consuming and somewhat complicated, but I'd do it again.
BTW, we also have a Kona Electric, but bought the Prime because we found the range anxiety and long charging stops on long distance trips (30 to 60 minutes, usually) exhausting. In our metro area the Kona is fantastic. The combination of Kona/Prime is about perfect. I've actually written about what I see as Kona limitations on my travel blog, thislandofjoy.com (Your Mileage May Vary).
Good luck to you!