I have no idea why most of ppl in this forum seem to go against Bose headphones, I mean, they are not necessarily the best IEMs in this price range, but they are definitely the ones worth every penny you spend on them. 
First of all, they are not 100% designed for Hi-Fi uses, if you are trying to compare them with UE18pro or IE80, then you are probably not on the right track. If you look into their design and spec, you'll see clearly that, neither their response frequencies nor the impedance is designed for Hi-Fi uses. then, what's so good about them?
What does Hi-Fi mean to you? for me, it's simply comfort and enjoyment of music. Being a professional company of great acoustics, I have to say that Bose has done a great job in their IEMs. The base you hear is not the strongest, but it still could make you feel your heart is popping out in every sec without any harm to your ear. the mids is a lil far away, especially for Soprano, which is kinda like a pity for them. 
Last but not least, they are very comfortable, I once fall asleep on a plane for 8 hours with them in my ears, and after that my ears did not hurt at all.
Therefore, if you dun really care about the trebles, they are definitely a good deal.