I have the Focal Clear's, and I'm extremely happy with them... However, I've been on the fence about "upgrading" to the Utopia, especially with the price it is currently at right now. Should I do it or should I not? Keep in mind, I can only have one or the other due to budget constraints. Maybe someone with both of them could chime in?
I also had the Clear and I just got the Utopia today.
I listened to it for a bit tonight, and after the first few minutes which were very harsh and sharp I've acclimated pretty well to the sound or the headphones burned in or whatever. Quickly switching between both using the Mojo and directly on my MacBook Pro (using ripped CDs) it honestly isn't that big of a difference at all. The Clear really gets most of the way there. It gets almost all of the way there. The main difference is you can hear a bit more harshness in the recording in some areas owing the the resolution of the Utopia so in some senses the Clear smoothing that out a bit is actually nicer. The Utopia sounds a bit brighter than the Clear which does sound slightly veiled in comparison, but again, this is really not a big difference at all.
My take is if you like to listen on either the Utopia or Clear for short periods of time in a more analytic sense to enjoy every last detail, then maybe it is worth it spending what you will with the Utopia. That's how I listen to my headphones as I generally prefer (even phone or computer) speakers for longer casual listening. However, if you are a true headphone person and want to listen for long periods for casual listening as well as analytic listening the Clear might even be the better choice being less fatiguing.
I auditioned the Utopia very briefly a few months back (I had the Clear already at that time) and my impression at that time was to pass as it did not really impress or stand out much at all (compared to the Clear as well as the Sony R10 which I tested it with back to back). However, I began reconsidering due to the Clear getting a bit uncomfortable just after 10ish minutes of wearing it (mainly with the clamp around the ears and also sometimes the hotspot on the top of the head). I read here that the Utopia would be more comfortable with softer pads and less of a clamp despite its heavier weight. It's too early to tell for sure but they seem a bit more comfortable. Plus while I really like the way the Clear looks and the color, I wish they had went leather. The gloss black Utopia also looks great, I kinda wish the cups just had the metal grille without the protrusions though (similar to the Clear).
I'm really not sure which one I'll keep just yet. The comfort will decide it. If the Utopia does indeed end up being a lot more comfortable than the Clear and perhaps separate itself some more soundwise, then I'm gonna pick up a Focal case (so ridiculously expensive but very nice) and keep the Utopia. If it runs into the same problem comfort wise, I will keep the Clear, as the sound benefits (so far) seem way too small and in some cases the higher resolution sounds worse.
This may sound like a downer post so let me just be clear, I think the Utopia is a great headphone, but the Clear is so good and you get the case and a reasonable length cable as well.
Just some last things for you to make my impression more valuable:
I'm probably not audiophile material (despite being able to hear up to 17-18 kHz) in terms of really analyzing the sound and all that, because although I try to do so, I also end up enjoying whatever it is I'm listening to. I'm most likely a guy who will end being OK with some decent headphones (50ish dollars) and happy with just one set of great ones, so while I'm enjoying the different listening, I think eventually I will return/sell off all but a couple of headphones. The only headphone left I really want to try is the Stax 009S (as well as the vintage Orpheus and Omega of course), and I will pick my favorite and just stick with it.
Though I'm far from an audio objectivist, I don't really hear differences between amps/sources in my (albeit limited) experience (I think I heard a difference switching cables more and I'm not even sure about that) so the notion that the Utopia scales better than the Clear probably wouldn't apply to me.
I like bright headphones (I think).
Aesthetics and comfort are very important to me.
Brand is also really important. I like Focal and Sony and Stax (and to a lesser degree beyerdynamic and Grado and Sennheiser).