I have the new series 2 version. I read the online reviews and issues people were having and were sceptical about them.
I have to say Bose have sorted the issues out with the cable ect, and have not personally experienced issues that the previous model had.
When I got the headset I played around with the different earbud sizes until I found a good fit. Putting the earbuds in your ear does take some practice, however, there are videos on the Bose website and Youtube on how to fit them, as they are the same as the sportbud models.
Overall, I am happy with the purchase and they have made my long sector days much more enjoyable with the Bluetooth capability