My humble opinion: pots. From my limited experience and also my understanding from reading and talking with more experienced growers, I don't think I'd attempt to grow Rocotos in-ground unless I lived in an area that was similar to where they are often farmed, i.e. 1) frost free, and 2) had a good portion of the year that had cooler night temps. For example, a Sacramento, California climate. Otherwise, your ideal daytime growing/flowering/fruiting temps for Rocotos are going to be in the spring and fall, when nighttime temps put the plants at the risk of frost exposure, therefore wiping them out. Also, in the summer, they have to be protected from direct sunlight and high temps when it goes over 95 degrees, so moving them to a shaded area and giving them morning sun only is necessary. Then when it gets cooler, it's best to have them back in direct sunlight again when the peppers are ripening.
Here's your weather by month in Lancaster. Forgive the messy lines, they were drawn with the mouse.
The times circled in green are going to be the best for fruit set. If you try for spring fruit set in ground, you could end up with frost. If you get fruit set in the fall, keep in mind that it can take about 8 weeks from when the first fruit sets until it ripens, so fruit that sets in September starts ripening in November. You'll definitely have to shuffle them to protect from November night temps.
I know that it probably seems like it'll be a lot of trouble but it wasn't too bad, and definitely worth it. The front of my garage faces generally south and gets full sun, so it's nice and warm in the front. Not sure if you have a similar microclimate readily available when it's cooler. I went to Harbor Freight, got a dolly and built a cart for me to roll them in and out of the garage on in future years. Definitely cage them (vs. staking) to reduce the diameter of the footprint for each of them, they'll get very wide (my de Sedas were easily 5 feet wide), which will help save room and make it less of a headache to shuffle them. Last perk: my final Rocoto harvest was around December 21st. Having fresh, home-grown peppers of any kind on Christmas is a blessing. I say pots, for sure.
Edited to add: I was going back through old notes a few months ago and saw that I had tried to grow Rocotos back in the mid-2000's, and just noted that they failed. IIRC they were planted in ground and died when it got hot and in full sun.