Well, here is the thing. The way I see it there is a two fold problem here...
1. With previous Intel chipset boards, you had a variety of chipsets some of which were considered high end, others mid range or mainstream. Take for instance P35 vs. X38 or P45 vs. X48. However, with the introduction of X58 there is only one chipset and every manufacturer is using it. This in turn dilutes the chipset's appeal as high end and it indeed makes it mainstream, that is for anyone who wants to or owns an i7 platform. Therefore, there is nothing really to differentiate the high end boards like R2E, DFI, or Giga Extreme from the average run of the mill boards like P6T, UD5, entry level DFI, MSI, etc. The only differentiation point is couple of bonuses you find on certain boards over others. That's it, and unfortunately that is not enough to call any board based on the X58 chipset trully high end. They are all high end (or rather mainstream now).
2. I would definitely not go so far as to say that other boards give better clocks. I do not think that they do and I have not seen evidence of this either. They all clock about the same in terms of the BCLK, they all experience roughly the same issues with memory, Uncore, etc., just depends on how much people write about it vs. how much they keep quiet. Yeah, R2E has some issues, but I do not think limiting the overclocks is one. Prior to BIOS 1104 there was a distinct advantage of running non-R2E boards due to the turbo throttle issue but this has since been resolved which now makes the R2E "just like every other board out there". Pretty crappy if you ask me, but an unfortunate byproduct of how Intel decided to treat Nehalem launch.
Pay close attention to the EVGA Classified now. I will bet you that not only will it not blow away the competition motherboards, it may still not even come out as the best overall board. There is no best if everyone is basically the same and the Classified will have to work with the same X58 chipset and with the same Core i7 chip. No surprises there, no miracles either. Don't expect that any board will give you "more" overclocking headroom unless you are maybe looking at the ultra narrow market segment of trully extreme overclockers going just for records and no stability at all.
Just my $0.02.