This is a thread that just keeps on giving (look at the dates)
Anyhow, I like the idea of using orange for all the LV, but the orange is hard to find and expensive. I plan to use 3/4" for my speaker cable runs, one 3/4" conduit for 2-3 speakers back to the equipment closet. Anyhow, to get 100' orange online can be $50+ To buy the blue stuff at the local home improvement is $30-$35. So I'll stick with the blue when I can.
For my projector - 2" orange, I'll get it online. For my screen wall 1.5" orange also online. But most of my 3/4" runs will be in blue, just to save $$$
But who knows, if I find the blue cheaper, I'll do that. For me color coding would be cool and all, but money is money