Thank you all for sharing your thoughts.
I should have mentioned that we plan to be using this pretty regularly. We are on the road weeks / months at a time. When we are remote, with minimal water options, we like to shower at least every 4 days. Historically, we take 2-2.5G showers each.
After a lot of consideration / research, we decided to try out the Big Kahuna with the heater kit. After we use it for some time, I will let you all know how it does. The reason we chose this option is that we wanted a hot shower without using any fuel (propane or isobutane propane), a 12V pump, an electric heater, and most importantly, it fits in the back of our vehicle. Yes, we could boil water to add to a bucket, scepter, or many of the shower options out there, but since we have 360Ah of batteries and 420W of solar, this seems like a good, portable option for us. Time will tell...
Thanks again.