We stayed here for two nights- we are a family of four- two children (7 and 2), and thoroughly enjoyed it.
We had booked online, but had to contact the hotel separately because the online booking site didn't have any way to say that we had children and needed extra beds in the room (even though the site described the hotels way of accomodating and charging for children).
When we booked, we were dissappointed to hear that we had a "mountain view" room, because all the "lake view" rooms were taken, and that they could only put one extra bed in the room because that's all there's room for (we didn't mind, because our two year old sleeps with her mum).
What a lovely surprise when we got there and found we had the penthouse room- yes it was mainly facing the mountains, but there were a couple of smaller windows the other side too, which had lovely lake views- AND there were TWO extra beds. I wonder whether we got upgraded, because it was actually an enormous room- we had a double bed, two singles, and lots and lots of space- even a lovely little balcony. And very reasonably priced.
Breakfasts were good, standard European. Boil-your-own-egg in a fondue-style boiler and take a timer to your table was popular with the children.
We had dinner there twice, and the restaurant is a gem, too. They sell fresh-water fish! Being next-to a lake, you might find that unremarkable, but we've visited quite a lot of lake-side places recently, and fresh-water fish is quite hard to come by in most of them. It was cooked and presented very well. They have a nice feature on their menu that you can choose between a small or a large serving size. And they had some lovely ice-creams for the children for afters, with a dinosaur cup that we could take home!
We'd go again.