I used to own the Shure SE215's and just purchased the Hifiman RE-400's yesterday. Obviously I haven't had much of a chance to put any hours on them but my first impressions are that the RE-400's are definitely a very balanced sounding IEM for the money. Some may consider them bass light especially in direct comparison to the SE215's but the bass they do have is again well balanced and proportioned with respect to the mids and highs. The Shure's seem a little warmer, probably due to the top end roll off and the Hifiman's may warm up a little with break in. The RE-400's do seem to extend at the upper end of the frequency spectrum a little more and that can be a good thing or a bad thing depending on the quality of your source material and ones personal preference. For the money it would be hard to go wrong with either choice. I don't personally know of any other contenders in this price range but with the proliferation of companies offering IEM's these days you would think that there must be some others that can compete and possibly even outperform these two models, but I certainly don't know what they are. Perhaps someone else here will. These comparisons and impressions were formed using a Creative Zen Player, all files uncompressed Wave, but I have recently purchased a FiiO X3. Since I no longer own the 215's it wouldn't have been fair to include any feelings I have about the RE-400's performance with the X3 in the comparison of these two IEM's.
I'll try to remember to come back later and post some further impressions of the RE-400's sound when I have had time to put more hours on them.
P.S. Although just by looking at them or judging by the lack of any heft, they are extremely lightweight, and considering the durability record of this companies previous models, you could be forgiven for thinking that these Hifiman earbuds will not be durable, but something tells me that with a little proper care they should hold up to all the rigours just fine. Time will tell. Oh ya, at least they now come with a zippered carrying pouch.
Edited by good sound - 8/11/13 at 1:04pm