I just got my new interchangeable needle set in the mail the other day, and I broke them out to knit this morning. I got the new Hiya Hiya sharps, small size set, 5" stainless steel tips. Wow. They are awesome so far!!
First, they came in a beautiful silk case, unlike the cheap plastic zipper pouch my KP Harmonies came in. The case has nice design features, like a Velcro flap over the needle holders, so you can open and close it, but the needles are still protect by an extra layer of fabric. There are 2 zipper compartments; 1 for the needle cords and 1 for the rubber grippies that tighten the screws.
As far as the needles themselves are concerned, I love how flexible the cords are. The cords for the interchangeable set are the exact same flexible clear cords that Hiya uses for the fixed circulars. Since I use the magic loop method a lot, these cords are great! I also like the nice, sharp points. I'm knitting a lace sock with the size 2, and the tips are perfect for the yarn. I think these are going to be great. I still like my Harmonies, but these Sharps are really nice.