I am a recent owner of a 21C. During our first extended camping trip, we encounter two issues which I required ETI's help. The first concerned the fresh water pump not shutting off when we were dry camping at altitude. We had limited cell service but I was able to contact Dustin. Dustin responded to my call that day.
The second issue was with the EMS which occurred once we were on 120volt service. Once again, I contacted Dustin who responded immediately.
Both issues were quick fixes once Dustin explained the issue. I am very satisfied with my experience with Dustin and ETI.