I bought mine on Amazon, which has a 30-day return policy if that helps you at all. I've listened on both iPhone with Apple dongle and my desktop system and I can't see anyone would want to attenuate the bass. The V-shaped sound, from rumbling sub-bass to intricate detail in the highs, is what makes them so amazing.

I don't love the stock tips, so I replaced mine with COMPLY Isolation TX-400 Memory Foam Tips, also available on Amazon. These IEMs are far from the most comfortable I own, but they're fine.

And when you say bias, I think you mean subjective and absolutely -- I probably have different preferences than OP. I'm sure both IEMs are fantastic and these take EQ reasonably well if that's an option for you.