Devil Sticks

I recommend buying from Serious Juggling. They're nice people, run a friendly business, have a good selection of devil sticks, and provide measurements of the sticks they sell.

I own:

Devil Sticks

Flower Sticks

Other

I've also tried:

plus lots of others I can't remember offhand, both mass-produced and home-made..

Hand sticks

If you're not working with fire, I've never seen anything better than the silicon covered sticks you get with most of the juggling-pro sets. Many vendors will sell them individually, so even if you make your own devil stick, you can get top quality handsticks for just a few dollars.