I also teach indoor TRX group classes and we use a mixture of the pro yellow / black ones and the force kits and we have yet to see a pro yellow outlast a force kit. And they dont stock all the sizes. like the sound quality. I like the length and how strong it is Boxes do not clip together and is super flimsy! It is optional. I also own AirPods Pro and do like those more because, mostly, for their active noise canceling. Great price, Love it in my laundry room. El producto esta perfecto, ese fue el unico detalle. My rack specifically was not brand new and has been opened.