Have had a Caldera Hawaiian for about three months. This spa has a 30amp and a 20amp breaker on the 50amp circuit. Twice I've had the 20 amp (which runs the heater apparently) trip for no apparent reason. Since it's in a cold climate and I'm gone for a month at a time, it worries me that the spa could freeze up, so I've had to have a family member come and check on it once a week. My intent was not to need a "babysitter" for the spa.
The dealer has checked it out and says it's got to be something with my power. Interesting, since I had a no-name spa on this same circuit for 15 years and never had a problem. I've contacted Caldera TWICE to see if they have had this experience with other owners and apparently their company policy is to ignore owners' emails. I've had one automated email response saying they'd get back to me and when I heard nothing for two weeks I wrote again. It's been nearly a week at this point since the second email and still no response.
I love the spa itself but am underwhelmed by the lack of response from the manufacturer. Hence, I wouldn't recommend this brand based on my experience.