i had another thought...i know you're curious to try the way the set works, but if you're concerned with cost, a slightly less expensive way to go could be to buy just one fixed circular options needle. i can't personally imagine using anything but the options needles. and as another slightly tighter than normal knitter, i'm not a huge fan of the harmonies (though i REALLY wanted to be), as apparently i just need the slickness of the metal. they're so pretty and fun though!
good luck with whatever you decide!
OTN: swallowtail shawl number 6, "cozy" blanket
merchgirl on ravelry
*i'm just a distracted potter who should be in the pottery studio: www.HeidisPottery.com*