I planted one callistemon rigidus (Clemson hardy bottlebrush) last summer, and it made through winter w/only minor leaf burn. It has been blooming intermittently all summer - it will interesting to see how it fares if we have a colder than normal winter.
Other than bullet proof Woodlander's red and a NOID weeping BB (which was killed by ground voles in it's 2nd season), this is the 1st BB that has survived a winter in my backyard. I don't think they're messy - have a friend in Biloxi, Ms, who complains about having to cut back their rapid growth at least once a year. I think this cold hardy BB would love your climate. Summerville is at least a 1/2 zone warmer than my area. They are hummingbird magnets, and lately I've noticed some type of small moth species swarming all about the flowers.
BTW, I was pleasantly surprised at how showy the flowers on my Woodlander's red were this year. With a little age (only a few years) the flowers are stunning. I posted a pic on the DG plantfile page. I think you would enjoy a BB in your yard, and I think rigidus would be happy in your climate.
i've never even seen a seed. the flowers fall in little pieces, a little at a time (think red threads). the seed pods or where the flowers were, hang on and become part of the stems forever. that probably doesn't make sense. i'll try and find a picture or else take one of mine.
ok, see this picture? the empty pods stay attached and where the seeds go, i don't have a clue. fall to the ground of course, but i've never had one pop up underneath.
You should be able to find nice size upright specimen for no more than about $25. I've seen Woodlander's red specimens priced @ $15. Think of it as a gorgeous hummingbird feeder that never has to be filled.
I've got a "standard" Bottlebrush that I got from either Woodlanders or Tony Avent about 25 years ago. Never had a single problem with it,of any sort. Just a beautiful, well-behaved tree, that is an eyefull every spring. Never had seedling problems (although I wish I had!), never had any problems with it at all. It just "growed like Topsy" and got prettier every year. It's one one my prized "successes"! I'd say try it by all means...theyr'e intrigueing plants!