***UPDATE***Month 1 after installing the unit, my electric bill went from $350 the prior month down to $230 the following month. So this has had clear and immediate cost savings for my electrical usage. Very happy with the results!----------------------I wanted to replace my traditional tank water heater with an electric tankless, so I did hours of research and comparing models and options. Finally settled on this unit in the 18KW size to fit my needs. I wanted to the next higher up but my electrical panel and home service capacity made that a risk choice. However, I'm delighted at how well the 18kw model works for my whole home use-case. Thankfully due to having an EV, I already had a conveniently located sub-panel installed. All I had to do was upgrade the capacity on that sub-panel, which was as simple as buying a larger breaker and making sure the existing wiring was up to the task. Ended up taking out the old 30amp breaker the tank water heater used out of the main panel, installing a 40-amp dual pole breaker there in its place, then upgraded my sub-panel to 100amps, and finally installing the second 40-amp dual pole breaker in the sub-panel. Ran all the 8 AWG wire to the location where I wanted to mount the water heater and used an appropriate amount of conduit and secured to the wall, which for me thankfully was only about 6 feet of distance. If you have complex electrical situations happening, definitely call in a licensed electrician. At this point it was an easy install to mount the unit on the wall, secure the wiring which was intuitive, and wall labeled. I didn't find any of the wiring or instructions to be wrong or confusing so thats a plus. The moment of truth then arrived, powering on the unit and setting the desired water temperature. A few quick tests and bingo, hot water.Its not been 3 days since the install and multiple showers, laundry, running the dishwasher, etc. No issues whatsoever. In fact, this unit outperforms the tank water heater we had before. My family now reports that they have to set the faucet to a less hot position than they did previous during showers. The water flow is perfect even when both showers are running full blast. We get consistently hot water and don't have to adjust it multiple times during the course of the shower as we did with the old water heater. Overall, very happy with the performance of this unit!My application is a single story, 2 full bath home, so I wanted something that could handle two concurrent showers and the occasional hand washing or laundry running at the same time. And I'm thrilled to say that it works for me better than expected. I also love that its a newer design that separates the heating element from the water flow path, which means less maintenance and easier repairs if something goes wrong in the future. Time will tell in terms of durability, but I was impressed with the quality of the build, its well-made and appears to be a thoughtful and clean design. Other units I checked out before buying this one looked sloppy, not as well designed. I'm so glad I chose this model.Obviously do your research on your electrical capacity, sizing for your use-case, etc. All I can say is that it works for me in my whole house use-case in Central Florida. Northern cold climates may need a more powerful unit. For me, I've got no doubt this will be more efficient and save me money on my monthly electric bill compared to the old unit electrical consumption. To top it all off, I got this on Amazon Prime Day using a deal and the cost was unbeatable for what I got in this unit. Super happy, will update the review in the future should anything else happen to change my mind.