To be honest, I've tought about switching to Nikon too. It almost drives me insane that it seems like Canon isn't doing anything about their (heavily) inferior sensors. With every release of a new DSLR you see Canon getting beated to death by Nikon and Sony when it comes down to DR....
Settle down. There is no need to go insane over a minor detail. 'HEAVILY inferior'?? Sorry mate, it seems you've bought the hype.
Thanks. I was thinking the same thing. Personally, I think this is all as silly as saying you're going to Nikon because they make their cameras blacker on the outside than Canon. I believe well over 99% of people using DSLR cameras today don't get anywhere near needing the theoretical DR that gets debated around here as if it were the damn holy grail!
Here's the thing: at ISOs 100-200 the sensor on the D800e is clearly, demonstratively superior in both DR and detail. These are not minor details. In a high DR scene there are times when I can capture the DR one on frame with the D800 that'd take 2 frames with my 5D2 or 5D3. That is not a minor consideration for some of us and could be considered a huge advantage (but I guess that's up to the photographer to decide). Regarding DR being a holy grail, well, at the point we are now with DSLR FF sensors in the 24-36 MP range already bumping up against reasonable diffraction (and processing) limits and with very, very good high ISO capabilities, AFAIC DR is now the holy grail (to be honest, it's been my holy grail since the 5D2 didn't much improve on the 5Dc & the 5D3 didn't improve at all on the 5D2, hence my foray into Nikon-Land). As for the argument (made above someplace) that nobody prints more the 7 (or whatever) stops of DR, tell me which file will make a better print: 1) one with very clean, detailed, noise and band free shadows and correctly exposed highlights or 2) one with muddy, noisey/pixilated and banded shadows and correctly exposed highlights? (caveat - that's a harsh description of under exposed Canon shadows but it is a situation that could occur in the same scene shot by the D800 and 5D3).
Now, at ISOs higher than the base 100-200 of the D800, the DR advantage is gradually lost until the 5D3 trumps the D800 (my experience seems to reflect the DXO Mark sensor test scores in this regard). So, if shooting at high ISO is a priority then sure, the 5D3 may be the better sensor to use. But don't discount the DR advantages of the D800 at low ISOs - they're real. And the detail advantages are real pretty much through out the ISO range when using non-diffraction limited apertures.
And before anyone dismisses me as a Nikon fanboy, I've owned the following Canon DSLRs: 10D, 5Dc, 1D2n, 7D & currently own a 5D2, 5D3 and IR converted T3i. And altho I own a D800e, I don't really see myself as a Nikon shooter and sincerely hope Canon gets its act together and develops new sensor tech to compete with the new generation of Sony/Nikon sensors so that I can go back to being a one brand shooter.