I have had mine for 2 months now and I have to say I am loving it.
In terms of the blind-spot, I can't say I have noticed it besides the huge side mirrors help a lot.
With the regards to the rear view, I have to admit I rely heavily on the sensors when reversing, but I do the same with the Mrs X5, so I would say nothing unusual.
How it drives is where the X6 is the strongest- dare I say it handles like the 3 series to me, just that it is heavier and bulkier.