Though bluetooth is a standard, some phones work better (or worse) with certain models of headsets. You may want to specify your phone model when you ask for recommendations.
If you want one to use primarily in your care you may not car about size. If that is the case I like my Plantronics Voyager 510. It works best with my 3 year old Treo 650. I get the least static (virtually none ever) and the longest range from the handset along with excellent battery life. No one ever asks if I am using a headset.
It can be found for ~$40 online. I'm guessing it is because of demand that the price is not lower. It has been around a while. The newer and smaller 520 is $15-20 more but has pretty good user reviews on Newegg.