After I had looked around intensely, I came across this small, perfectly adequate assortment of me until then completely unknown company "wedge" here at Amazon. The price seemed low, but the nonexistent reviews kept me at first from an order. So I researched and called the regional distribution (wholesale) from Keil to. There I learned that in our residence (Quickborn near Hamburg) has an active sales office. There I went there directly to get some advice. It turned out that this previously unknown to me Keil provides a very high quality and mainly for professional craftsmen should be a household name! But they did not want me 5er drills, but only from 10 mm in stock. When I told of this set on Amazon, you wanted me there do not believe I can buy at this price.
Long story short: After today's test use in the bathroom (tiles, behind massive stone wall) with a cordless impact drill with 18 volts I am absolutely thrilled! Already alone the packaging, a kind of durable slipcase acting, not hard plastic is a big difference to the unprecedented Baumarkt-goods! And the drill itself look like ten times as expensive as one of those silver BOSCH Concrete drill bits, which are also present here on Amazon in various sets again. So people: buy buy buy !!!