Here is another good 6D review

Conclution:

the Canon 6D is so impressive that I would consider buying one and adding the Can0n system to my bag, even if only for certain kinds of work.  For the hiking, backpacking, and traveling that I like to do, this is one of the best cameras I’ve ever used

http://www.slrlounge.com/canon-eos-6d-dslr-review-and-field-test-canons-highest-quality-dslr-yet

In my experience the 6D focuses amazingly well overall. Sure, the non-cross-type off-center focus points aren’t going to be as reliable as the clusters of cross-type AF points on the Canon 5D mk3 and 1DX. However the center AF point does not disappoint, even in terrible light that the likes of the 5D mk2 would frequently choke. I found myself trusting the 6D to nail focus far more consistently. Even the off-center points can be trusted in moderately poor light, especially if you memorize which direction each AF point is sensitive to detail in.