I was so excited that I found an in-ear BT headset to replace the 640 I lost (maybe I should get something bigger not smaller). I took the Nokia BH800 out of the box and after it fell out of my ear 5 times in 2 minutes I looked for the gel that attaches to the earpiece so it will stay...all they give you is a piece of wire that looks like a coat hanger to help support it. I was so dissapointed - my 640 came with 3 different size in ear gels to ensure proper fit, each molded to fit your ear. I was not alone in the problem either as two others in my office could not get the thing to stay in their ear. They should say you WILL have to use the coat hanger all the time. The fit of the loop is just not sound - it looks like an afterthought.
Sound quality is fine, did not have much time to even test the calls as the darn thing never stayed in my ear. I guess I could try to "fit" a Jabra gel but for 140.00 you would think it would at least come with something.
If you are looking for a real "in ear" headset, be careful with this one..
Now that I said that, I returned it and got the Jabra JX10 - very similar product but I am a sucker for dissapointment

. Thankfully they made the earpiece a bit different and it sits VERY well in my ear, more a result of style than my ear as again the two others tried it and both had sucess with the Jabra staying (one is a female and the other a larger male). Also, the attached ear loop is MUCH more usable. I will use it w/out the loop though for a while to see how it does (it passed the head shake test and did not budge). It also comes with a great charging base which is sharp...plus it comes with a USB charger so you can leave the base at work and bring the short USB cable home.
Sound quality on the Nokia seemed a bit better, but not nearly enough to offset the fact that I had to hold it on with my hand. The Jabra is clear sounding w/ no static up to about 15/20 feet away (lots of "stuff" in my office too that tends to compete with signals plus we are in a busy office complex). Both have DSP, we will see how that does later on the way home. Volume inside was very good and loud
THe JX10 seems to be what it is, a small and very lightweight yet "fashionable" BT headset (as fashionable as anything sticking out of your ear can be). Yes it cost a lot, but at this point I was more interested in being able to quickly grab a call w/ one hand and not worry about wrapping anything around my ear - and it had to be small enough to fit in any pocket.
I don't like to bash products, like I said I loved my 640 but they were out of stock and I heard so much about the Nokia I had to try it. Overall my first impression of the JX10 is fantastic, I would never recommend the Nokia.
my two cents - keep the change