I've used Bodyglide pretty much exclusively for a couple of years. It works for me both thighs and nipples, and I also sometimes use it on my ankles when I have a new pair of shoes - seem to rub there. I tried SportShield from TwoToms and that worked well too but it's a liquid and so when it fell sideways in my gym bag it leaked all over the inside. Since it didn't seem to work any better than BodyGlide, I just went back to that.
One downside to any of these products is that they will stain your shirt - I have several white technical shirts that now have brown stains where I put this stuff over my nipples. So be careful if you are wearing a shirt that's important to you! I ruined my Inaugural Rehoboth Marathon shirt that way.
I'm new to the world of Body Glide (new to marathon training as well); it wasn't until I got past 8 mile runs that I thought to ask friends about chafing in various areas....I'm now up to 12 mile runs and still using Vaseline or Aquaphor (similar to Vaseline but water-based) cuz there are so many Body Glide products I'm not sure which to use. Is one better for, say, nipples, and another for inner thighs? Is there one that's all purpose?