Mac, they're not too figure hugging at all. I have had Mediums from other manufacturers that have been more like compression garments (except that they seem to accentuate my gut, not hide it), but these are rather more like a polo shirt in fit.
I'm 5'8" with approx 40" chest, and the Shutt in Medium is a very nice, relaxed fit - like I said, could almost be mistaken for civvies.
3bikes: As for the feel of merino - it's nothing like any other wool. Next to the skin, it feels more like a cotton/polyester mix, except that it doesn't get soaking wet like cotton does, and doesn't stink like polyester does.
- Darren