Hi, I need some recommendations for a pair of IEMs.

I have a set of Sony 7506's from around 1990 and V6's from about 8 years later that I bought so I wouldn't have to carry the 7506's back and forth to work.  I love them.  I'm sure there are more expensive sets that might sound better, and some people find fault with them, but the clarity, balance, detail, everything I can hear with these, is what I'm looking for in an IEM.  Is it possible?  I've never heard any earbud/canalphone type headphones that sound remotely close.

 I got a pair of Sennheiser CX300-II as a gift recently, they were purchased at Best Buy, and they're just horrible.  The sound is just muddy, vocals disappear into the mix.  There is no detail.  I really expected a lot more, judging from the reviews I read online.  I later read that fakes are common, but these came from a major retailer, and there's nothing about them that would make me think they're not real, except the lousy sound.  I listen to rock, funk, jazz, fusion, that type of thing.  If Aja sounds good, then I'm happy.

So how far up the scale of IEMs do I have to go to get something that will produce similar sound quality to the full size Sonys?  Stores don't exactly let you try them first, so all I've got to go on is other's opinions.  I've looked at the giant IEM comparison thread, can I expect that anything with a sound rating above some number will be good enough?  Should I just order the RE-0's?

Thanks,
Greg

Of the top of my memory, the impression on V6 and 7506 are more treble oriented and focus more on clarity.

RE0 might sound thin when unamped when compared to the two, I think getting RE-Zero would be a much safer bet.