Well, I went out and collected my 4C from the UPS depot. Got wet and my train got suspended, but I got it.
Not had too long on it, but even after coming from the K10, it still wowed me. There are a couple of 4C/4S reviews on here (Joker and Kunlun) and they do a much better job than I ever could. Compared with the K10, it has a bit less bass that although it doesn't really show up on most genres, it was noticeable on electronic/dance.
I run the 4C from the Sony ZX1, and like my K10, I find I don't need to do any sound adjustments/enhancements. I was pleasantly surprised by the 4C. It's described as neutral and flat and this is something I've not gone for before. Plus, with the K10, I was worried it would dominate the 4C in everyway so much so that I would not use the 4C. It's still too early to say if this will be true, but I'm positive this won't be the case. For outdoor use, I will stick with the K10 as the added bass is needed.
Edit: Regarding UPS. GRRR, they make me
. They told me the address was incomplete, but I when I got the parcel, it wasn't. UPS's service really seems to go down during busier times.