ya that wi fi on the board is just one more thing to go buggy and a USb wifi adaptor is cheap and easy to use
I like my extreme 6 z87 I'd say it been one of the better boards I've had in some time
seeing you don't have a ''K'' cpu and if you don't care about running NVidia SLI you may not need a ''Z'' board any way
thing is what ever one you decide on theres all ways that chance of getting that lemon , that's with any brand . you buy what YOU feel is better for you and your needs and build it and fire it up , it will work as you expect and run stable or it don't