Some Sedums are tender house plants but many others are 'tough as old boots' and can even be considered invasive. The outdoor ones prefer a poor soil and full sun; no problem with winter. I like them.

Waddy - I love sedums and the only problem I have with them is that I find is my soil can hold too much moisture for them. As bulbaholic says poor soil - good drainage is important.
I have better results keeping them in pots - they still do well with no maintenance and very little water and absolutely no feeding!

I love sedums too, tough plants, always flower well in my well-drained chalky soil, and the bees love them.

Thanks everyone, I'll try to put some pics on of the developments of the Sedum Bed as it develops :0