Can circulars totally replace straights?
 

that is, can I do away with spns and dpns.

Well, technically yes. You can use magic loop or two circs in the place of DPNs and of course you can use circs in place of straights. Now that I learned how to use DPNs though I prefer them for some things. I'm still learning though.

Circular needles CAN replace straights. They are awesome for bigger projects such as a blanket or knitting wide panels. But you can knit back and forth on circ's like you do regular straight needles, you don't connect though.

And the best part about circ's is that you'll never forget a needle! ;)

well i think you are still going to want to keep your DPNs around for things like icord at the very least....but i have never bought regular straight SPNs...never even attempted to use them.

I use circs almost exclusively...like bren said, my dpns are the only other needles I use. As a matter of fact, I'm going to order some of the cool new dpns from knitpicks...and the interchangeable set ;)

Yup.... I only use circs and DPNs. In fact, when I have tried to teach beginners' classes at the LYS, I ALWAYS drop the right needle! :roflhard:

I guess so, but it's something about the "tradition" of straights that keep them my favorites.

I use circular needles and dpns almost exclusively, but straights tend to be really good for intarsia!

Why do you want 3 interchangable sets? Are you like me a shopping addict, or it is necessary for certain projects?