Sturdy headphones, no manufacturer warranty support
The MA750i has great sound quality and is solidly built. They are not lightweight - the earbuds are made from aluminum and will feel noticeably heavier than plastic earbuds you have tried before.
Note that if you try to get manufacturer support after buying these on eBay, you will not be able to. I broke my first set within 2 weeks of purchase. It was my fault, I dropped them into a bicycle wheel... something no earbuds would survive. Because I did not purchase from an RHA authorized reseller (Amazon and a handful of private shops), I was turned away by the manufacturer. But, the price was good, so I bought a 2nd pair.
Verified purchase: YesCondition: New