I am a complete nut when it comes to TV for kids. My almost five year old girls have seen Dinosaur Train, Sid the Science Kid... and Project Runway. Seriously. I will not let them watch most kids shows, or any commercials, and they've never seen a full length movie, but I think Project Runway is just fine. The comments about body parts are just that... the designers are not sexualizing women, they're simply talking about the body parts they're designing for. And yeah, every once in a while there will be the occasional bad word -- but not even one an episode. And they do fly right over my kids heads (but I'm not all that worried about language - I can explain what the words mean and why we don't use them if I need to).
My girls don't watch Project Runway all day every day, but when they stay home sick and I can no longer read books to them, I will turn on a recorded episode for us to watch together. Oh - worth mentioning... some of the seasons are better than others. The current one - the All Stars, is not acceptable for little kids, in my opinion. The contestants are really catty, and I don't want my kids watching that.