I had the same dilemma.
I find the reviews on cnet.com to be the most detailed you’ll find. And they do give plenty of negative reviews, so I don’t believe they’re overly biased.
That being said, based on the largely positive view of the sleek (and expensive!) Jawbone Prime, I bought it. It’s beautiful, but I don’t think its sound quality is anything special.
If you’ve never had a Bluetooth headset before, you won’t even know if you like the idea of using one, without using one.
I would say to buy the most inexpensive one you can find, from a store that has a liberal return policy. If you end up happy with it, great. If you hate it, return it. If you like the idea of using it but you’re dissatisfied with the quality, return it and spend more for something better.
In the car-audio department at Wal Mart, there are three Bluetooth headsets that look to be pretty much the same, for $20.00 each. (The headsets in the cell phone department are pricier; only the car audio department has the $20.00 price level.)
I have no experience with those $20.00 headests, so I can’t say much as to their quality. But it might be worth that small investment just to at least try one out and see if you like it.