I`ve got the Plantronics / Altec Lansing Backbeat 903. For just under £50 I`m well happy with them, the earbuds are not the "completely in ear" type so they don't filter out all the outside noise. I prefer that as I don't want to hear my heart or every step I make when listening to music. Sound is great imo for earbuds headphones, it maybe lacks a bit with tha basses but otherwise I`m happy. In-ear pieces twist and extend so they are adjustable, I was worried about the cable catching the collar but it`s fine, I was after a complete freedom of movement and I`ve got it. Regarding the signal, they work very well outside (meaning continuous playback without any cut outs) as long as I keep the N900 on the right hand side of my body, usualy in a over the shoulder bag, I suspect the antenna is in the right hand side piece. Battery life good, charges quickly, sweat proof, well recommended.