I like the interchangeable sets from Knit Picks
http://www.knitpicks.com/needles/Kni...__L300301.html and WEBS
http://www.yarn.com/webs-knitting-ne...able-circular/. Both offer sampler sets that include tips of the various materials. Right now I'm trying to convince myself I can afford to order a set of the wood interchangeables. I like the way the wood feels but mainly the points seem sharper on them than on the metal ones; otherwise I like them both. I don't like acrylic.