I'm loving these IEMs more and more after I changed the tips. Ever since I used the blue (I believe it is the medium ones) with the foam inside. I used it because I think it is the medium size, and all IEMs I've used so far has the greatest seal for my ears with their medium-sized tips. I used the one with the foam without comparing the sound to the other without because I think it would be much cooler to use as I've never seen one before lol.
I've been using the tips more than a month I think, and I always have this muddy and fat bass complain. Until yesterday I tried to experiment with the other tips. First I put on the blue without the foam and I was shocked by how different it sounded. It really cures the muddiness of the IEM and made me swear that I will never use the tips with foam again (at least for this IEM lol). I can hear the cymbals better and they are more distinguishable to other cymbals used in a song. The highs really improved. Then I used the green ones (again of course without the foam), a little smaller from the blue. Now I felt how cheap the GR06 is for its performance. The highs, it's slightly better than the blue but not that noticeable but the speed really increases and it is very important to me. The bass is not that thick anymore and it's fast enough for my requirement. (believe me I hate boomy or sloppy bass more than anyone lol). The mids are now more neutral and not that kinda over-emphasized mid-bass feeling I get on the blue with foam. It's very very nice that it makes me feel very happy and at peace whenever a song that requires good mids plays in it. The green being smaller than blue resulted in just a little bit less isolation for me but there's no problem as long as I get the sound I want. It isolates well too though not just as good as the blue. There is no need for this kinda long story of my discovery of the right tips for me I just find it cool to post it here lol.
But anyway the point is, always find the right tips for you, don't just settle for the one you already got used to. Especially when you don't like that much the sound you hear, it is really really worth it once you find the perfect ones. I know many others have already said that, I just feel I need to say it too. :)
But they still only sound pretty mediocre even with the perfect tips. The clarity and detail is only average.
With the plug-in TB EZQ + J rivers crossfeed they sound better than many 150$+ in-ears I've head.