I wanted to like these earbuds, I really did, but I ordered them for doing Teletherapy during this COVID era and in the end, I went back to my tried and true Samsung earbuds. Used this ski rack twice on 2 1300 mile trips. Assembly was a breeze, and I love the multiple shelves to accommodate lots and lots of shoes. I?m not sure of the Bluetooth on the 500bts (I?d love to compare them) but it?s not a feature I would really pay extra for due to these. I store most items in baskets- heavier baskets are balanced on the rods and not the fabric. I will update again after a few more days. They?re actually more comfortable, but they?ve significantly altered the air chambers, causing my interior microphones to go haywire. The pad density is exactly right, and theyre sonically transparent. Per my previous edit, Im wondering if this has to do with the fact that I received the original Mush instead of the Mush II (as ordered)? It fit on the roof rack carrier an made the trip a pleasure, leaving more room for the dog- bed an dog.