Jan - the one in the web page you gave -they have got the name wrong (as often happens with plant names), it should be SEMPERVIVUM.
S. tectorum and S. montanum are well known species, flowers are all very similar and pink.
There are a lot of different species, and also quite a lot of hybrids, names like: Lipstick, hey-hey, lively bug, Kramer's spirad, etc.
They do very well in terra cotta pans, old sinks, and containers which don;t hold much soil, but must have drainage holes and if given plenty of direct sun should grow well and flower.
Reddish ones are attractive.
