Yes, I've had some for many years and they are totally hardy. Like most of the plants we grow, they prefer humusy soil and regular moisture, sun or part shade - other than that, no special needs that I've seen.
The species I've had the longest and my favorite is Astrantia carniolica 'Rubra' (since pre-1999; i.e. from before I transferred my records from plant markers to an excel spreadsheet!) - it appears to bloom through the entire season. What I mean is that it starts to bloom in late June and goes for a very long time, and even when the flowers are no longer fresh, they retain their color and shape right through to hard frost. I like the dark pinky-red and long bloom of this one, particularly.

Also have had a couple of selections of A. major ('Roma', 'Sunningdale Variegated') for some time - also hardy; I find the lighter colored flowers (pinkish, whitish) on these turn turn brownish when they are spent, so rather less interesting...but still certainly worth planting.
The foliage is also nice-looking, with interestingly-shaped leaves that provide a nice contrast in the border.

My advice? Buy them.

Heh. Doesn't take much to convince me! LOL Thanks, Lori!

Vesey's has "Ruby Wedding", "Snow Star" and "Roma". And they sell them as a collection with a savings of $5. They're on the list!

marciaz3, I also have 'Sunningdale Variegated', in which has been totally hardy. The foliage is most attractive in the spring and becomes less colorful as the season progresses. I agree with abgardeneer, that the blooms on this one are not terribly outstanding. My plants are situated in moist fertile soil where they do very well, though the flower stalks tend to get a bit floppy. Over the years I've found many seedlings popping up!

Terry

Thanks for the heads-up on the floppiness, Terry. I'll keep an eye out for that. I had so many floppy things last year because of all the rain we had in June.

I'm sold on the idea of these guys - hope they come through for me!

Another one to look out for this year is A. 'Moulin Rouge', dark red flowers with purple-red tips.

Here is a link that might be useful: Astrantia 'Moulin Rouge'

There were quite a few new-ish varieties in the stores here last summer, including 'Moulin Rouge' (which, by the way, didn't look so vivid in the stores in pots - like most plants, gotta get them in the ground to tell).
Haven't found any of my astrantias to be floppy, despite all the rain last year.