I am planning on buying Bluetooth in-ear earphones for every day use with iphone 7 to use on the side of current Sony MDR-XB50. Considering to buy beats x (which are on sale for 100 euros in local apple store). My question is - how's the battery life and general build quality of beats x in long term? Don't want to buy something that will fail in 6 months, as the sony ones have been doing very well for a year already (and cost a fraction of beats). Or maybe you have any other earphones to suggest (under 100 dollars).