Been using the Petitjean bobbin for about 6 months now. I have dozens of other bobbins, but they all sit empty now.

http://youtu.be/g_zs67JjZsE

Adjustable thread tension (while wrapping!), fast threading, built in dubbing loop feature, perfectly balanced when spinning - this bobbin does it all!

It's so quick to thread, you only need one bobbin - good thing - they're like fifty bucks.