The X9 looks a lot like a Motorola headset and also the Nokia BH-505.
I haven't tried any of the models here, but I've spent over $1k on trying to find the "right" BT headset for me (spend 5-9 hours a day on the phone).
Ended up choosing the Nokia BH-505. Very few problems, pretty comfortable, good sound, great talk time and range from the phone. I will say that after about four hours straight wearing/using it I can get a bit of a headache if I don't take a break, but most of the others I tried couldn't even work that long.