We used this to replace a Rheem Integrity instant hot water unit that stopped working after almost 15 years. Good instant hot water, but will give someone a jolt in the shower if you turn on the hot water tap somewhere else. It has good water saving, it drops the pressure while it starts to heat up and then as the water is hot, it increases the pressure back on the line. The first time it happened, it was a bit of a surprise but this is great because it doesn't waste water while it's getting to temperature. Since it was a replacement of a similar unit, it even used the same mounting hardware/holes. As always, Appliances Online for the win again.