While I do not usually write reviews, I thought I'd write one up on these headsets as it has taken me quite some time & research to find a pair that get it right. While not perfect, the price/performance ratio is spot on, and you really do get a decent set of headphones for around $150.
No reviews noted my highest performance test, shielding the headset from outside RF/other interference. I commute daily in NYC, and while walking the City, especially through Times Square, my Motorola Bluetooth headset was unacceptable for use. Just listening to music was impossible, as they were very prone to interference and would cut-out. That, and they never fit just right, and would slide down my neck a bit. They are now on eBay :-).
These Sony-Ericssons? Perfect. Not one dropout or any interference during the entire 10 minute walk from the Port Authority. For this alone they are worth the cost of admission.
I pair them with a Blackberry 8830, and switching between calls/listening to music is automatic and flawless. Not to mention they are super comfy...I never had earbuds fit so well that I forgot they were on, and they are the best I ever had at blocking out outside noise. They can be used as earplugs if you are using a jackhammer!
PROS: Very good sound and comfortable fitting plugs. Great easy to use carry case, no bigger than a lens cap case to protect your investment. Easy to use and pair (at least with my Blackberry). Very good sound quality for both the caller as well as the wearer (calls made in mid-town Manhattan at Noon were clearly defined and made without incident). Superb isolation from interference (I think Manhattan Time Square area is the RF capital of the world, and it never affected the headset, not once).
CONS (all minor): While they come with a small clip, I worry about losing them (falling) from my neck if not in my ears. Not a big con, but be aware, as they do cost $150. Also, as mentioned by the first reviewer, you do have to be delicate while opening the charger port, as the cap is only held on (while open) by a tiny plastic hinge. Roughnecks will break & lose the cap, I'm sure. The sound from my Blackberry is a bit heavy in the bass response, but I am sure a bass level or electronic equalizer (if available on your device) would clean it up. As the Berry has no such controls (on my version of the software), I am stuck with where I am (not terrible, but I'd love to be able to tweak it a bit...I'm a tweaker by nature!). Finally- the charger is proprietary (I know, what isn't from Sony), so you'll have to take it with you (small gripe, but it would have been nice if a USB port had been incorporated in order to charge).
In conclusion, you won't be sorry with this purchase, even with some of my minor cons. Sony would do well to either include or offer replacement caps for peace of mind; perhaps in the future. For now, you have to be careful. Also note I haven't had them long enough to comment on battery life, but if they fall way under or over the 2.5 hours the specs note, I'll add to my review.