Bernd,
I found them very reliable and for the money, very good quality. Plenty good enough for what we use them for. I use both the two and four flute cutters, in both HSS and tungsten, and I also have a full set of the ball cutters, and all have performed perfectly satisfactory in the general purpose materials we use.
I did the same post on HMEM, and they started to complain that the Rockwell count wasn't as good as top quality stuff, and the slot drills were slightly undersized, etc etc.
So I left them to it and left the site. If they are too idiotic to realise that these are not the same as top quality ones, then they are not worth helping.
All I can say is like a lot of things I recommend, most times they will be a lot cheaper than elsewhere, and plenty good enough for what we do. You will always get some people that don't like what I recommend, but more than enough class them as a bargain, that those people can basically be ignored, as they will NEVER be satisfied unless they can boast that they only use the best that money can buy.
Bogs