I'm a pretty large dude, 6' about 215 lbs and have always done a lot of strength training. About a year ago I got "talked" into doing yoga, and I continue to try to make the class once a week ever since.
It has definitely helped on my flexibility, increased strength in many of my lifts (especially legs), and best of all it has increased mobility in my hips/abs, which my girlfriend get's to benefit from, if you know what I mean

. It was a little discouraging at first because of my lack of flexibility, but I have definitely made progress over the past year and it has helped to reduce my overall stress. I also feel more athletic when I run and play sports. Did I mention it helps in bed, lol.