If it's "perfect" sound quality you're after my friend, I'm assuming it's sound being reproduced in it's purest form that you're referring to, without coloration or any one (or more) areas predominating another. While nothing is perfect of course, the Westone 4 is about as close as I've ever come in the realm of universal IEM's. As per the name, it's a quad driver, of which 2 are dedicated to the low frequencies, and the remaining 2 dedicated to the mid and high frequencies. However, don't let that mislead you, as the W4's are channeled much more towards quality, than towards quantity. Not to mention, they are easily an all-rounder, and are fit for any genre of music IMO. There's certainly enough bass impact present, which is easily appreciated when the track calls for it, but it's not at all overpowering, nor are they geared towards bass-heads. Sure, there's other top tiers that may satisfy your ears, but to my ears, the best of them in terms of presenting the sound in it's purest form, is quite simply the W4.
P.S. Before the infamous Head-Fi pirates jump my ship (if you think it's you, it's probably you ), I'll mention that no, I'm not suggesting the W4's to the OP only to attract a buyer for my own pair listed for sale. As a matter of fact, I'd strongly recommend that s/he buy directly through a certified reseller instead, in order to ensure full warranty coverage. IMHO, the W4 represents the purest of SQ amongst all the universals I've personally come to own, and that is my only reasoning for my suggestion. They've been sold new for ~$380 for quite some time (through soundearphones, after 15% off) in the past, and can definitely be acquired sub $400.
P.P.S. As our friend calipilot227 mentioned, the ER-4, as described by the many listeners here at head-fi, also sounds quite fitting for what it is you're after; though I personally haven't any experience with them. Fortunately, you'll find many in-depth impressions/reviews through a simple search. All the best my friend, happy listening!
Edited by i2ehan - 6/27/11 at 4:31pm