I'm still not overly convinced storm troopers are worth their points but word from Imperial Guard high Command is "Storm Troopers, dey tha bomb, yo!" so they're probably worth giving a go.
I've used Pig Iron Productions models for mine as I've been trying to find an excuse to use some for a while now. They're painted to fit in with my Praetorians, more or less. Also realised halfway through they'll match my Witch hunter scheme too! Good work me!
The camo was done using the sponge technique, similar to vehicle weathering, with scorched brown and white. It just about works although some look like they've doing a spot of DIY before kitting up for patrol! I'd definitely try it again anyway.
The Sgt has a "Ramshackle games" head which has a (golden) face mask. I had planned to give them all similar heads but when I got all the bits decided the Pig Iron heads were superior.