Yeah, I was a sucker and got a Jawbone (paid $70) and I have to admit I'm very disappointed. It disconnects from my phone all the time, I never know if on a new call if the headset will be available, noise canceling doesn't work in my Jeep (didn't surprise me but...), the two buttons (and combinations) are hard to remember and push and even with the different ear attachments it still fits loosely in my ear. For $70 I was really hoping for better.
Wow, dude, you must've gotten a bum unit. Everything I've heard about the Jawbone has been positive.
I personally have a Jawbone and it has the best noise cancellation I've ever come across. My car is a rice rocket with a loud exhaust and people can't even tell I'm driving in my car. I've never had problems with the Jawbone disconnecting or connecting. I can leave my iPhone inside the apartment, walk about 15 feet outside, have a smoke out on the balcony and still have an awesome conversation through the Jawbone.
Try bending the ear attachments to get a good fit. I got mine to fit nice. It's just a pain in the ass putting it over my ear.