Apart from the fast delivery as always by Amazon convinced me of the heater with its power fully. Now me is always hot water available upon request. The installation was carried out by a specialist, however, took a little longer than indicated by some Mitrezensenten. Visually, I find the water heater ok, it affects not puny. In addition to the affordable price, what more could you want. The predecessor was also a Siemens device, however, hydraulic and far less comfortable in his performance. But he held for 20 years. When the new water heater would have a long life, I would be very pleased. So my recommendation is to buy the unit.