Altones have good bass punch but their sweet spot is upper mids and upper end. Either you like to hear detail in that area or you don't. I like them, but source matters, and so does source material. They sounded very good with my DX50/JDS Labs C5 amp but too trebly with my Fiio X5. However, they sound very good with my Fiio X1. What music you play matters as well. If you have a lot of music with "difficulties" in the upper end, it may be too much with the Altones. But with well-mastered-and-mixed material, they can be fantastic. It's a matter of preference. Some like them, some find them ok, and some really don't like them.
I like them.