Yeah if it's strictly winter go 5mm neoprenes. It's best to be able to try them on before buying, and try them on as you'll be wearing them out in the field. That is, the last time I was buying waders at basspro I yanked a pair of socks off the shelf, put them both on one foot and then made sure it would a) fit in the stockingfoot and b) everything fit into the wading boot.