Hi, just wondered if any MN knitters can advise me on interchangeable circular knitting needles. I don't want to make a costly mistake but I really like the look of the sets ( knitpro, addi etc) and basically wondered which is the best brand, which kind are best (bamboo, plastic etc) and wether it is worth actually buying a full set or just a few common sizes first and add to my collection later if necessary?