Oh, there's no doubt that it can work great when it's working... but when a bad adapter is capable of crashing a router, even the wired side, then that tells me there are still serious software bugs in the router's firmware. At the very worst case, some sort of watchdog timer ought to have kicked in and forced a hardware reset.
It'll get better, though... I tested an AC router with beamforming, and that performed VERY well. It's just too bad that the firmware crashed on the 2.4 side whenever I entered a WPA passphrase that had a space in it.
Then there was the failed firmware update on another router... I simply tried to upload the latest firmware, and the thing bricked.
On the bright side, after buying a gigabit switch and string more Ethernet cable (something I was trying to avoid), my current setup screams. Sometimes, that's how you fix your wireless problems: wire it.