I love my oly lifting nike romaleos, but they are heavy. The new adidas adipowers are much much lighter. They are great to help with ankle flexion and creating a solid base for your squats. They are both pricey, but well worth it IMHO
I squat in Oly shoes, to be specific I wear Adipowers. I'm a semi wide stance raw squatter. The heel has the greatest transfer of energy b/c it doesn't compress at all.
Chucks are better for deadlifting IMO because the canvas has a lot of give and if you pronate or anything there isn't much protection of the ankle if you are walking your squats out.