I made a bunch one year and kept a few and gave many away. Here is a link to my GardenStew blog http://www.gardenstew.com/blog/e5463-20-making-a-living-wreath.html for making one. Easy to make. They do take quite a bit of maintenance and kept away from squirrels and jays that can destroy a wreathe for food, and nesting materials. My ivy wreathe has held up the best. Once semps have bloomed the parent plant dies leaving the babies and a bare spot/hole. Mine were as cold hardy as the semps and sedums. You could store them in a cold frame to moderate temperature for extreme weather I would think, but I did not since our temps don't stay cold (15F) for very long.
Some of the sedums you have pictured should be very quick growers. You will be able to start pinching the ends and potting them up sooner than you think. Sedums root quickly and multiply fast. Although I got tired of mine and after a few years started neglecting them I have plenty scattered around the yard and in various pots. Later this spring I will see which ones are still hanging in there and resserect them as ground covers in potted patio trees/plants and center pieces under glass patio tables. It is amazing how many escaped and now find homes in edgings around the patios and walkways.
Thanks for the reply Jewel. I'm hoping they grow fast. I'll have 3 whiskey barrels and an old fire pit full when I get them all planted. I'm hoping to get to make a wreath later this summer, but we'll see.