Different needles will also give you different gauges sometimes. I've never used any wooden needles except ones my husband made out of dowels from the hardware store. They were not so hot. Bamboo is a little slow with some yarns but just the thing if you need a bit of bite so things don't slip around. I like the nickle plated ones I have and aluminum have their place as well. I have never used and plastic ones but have a lot of old nylon circulars that I use all the time. They are not as grippy as bamboo, and not as slippery as metal.