@Jontu and @Mmumm my Dyson stick is 3 years old and always on charge in the holder. I haven't noticed any deterioration as yet in battery life. However I expect it would happen eventually as it does with any rechargeable battery!
@Tamtam no the length is not adjustable. You can put the motor head directly onto the handle part and it looks like on of their handheld models. I'm pretty short (158cm) and I don't have a problem with the length. DS1 who is 191cm has not ever complained either 😊