We've been traveling with a couple of Gitzo GT1555T Series 1 Travelers with RRS BH-30 heads for over a year. We certainly don't use them with long lenses or heavy combos, but for everything else they're fine.
I'm 6'4", so my center column is extended a lot of the time. I'm concerned about that while shooting any shutter speed is in the 1/8-1/2 second range, but with with today's better performance at higher ISO, that's usually a workaround. With lighter camera/lens combos, hanging a little extra weight from the base of the center column really helps, especially with breezes. So does use of a cable release. I haven't had to resort to mirror lock for any situation yet, but am prepared to do so.
The trade-off is lots less weight when traveling. That's enough benefit for me to use workarounds. At only around 3# for the legs and head, it's so light I carry mine all the time clipped horizontal onto my camera bag. As a result I've had it along when unexpected needs arise, seldom the case with heavier tripods even at home.