re(4))
I didn't test X.org, just booted FreeBSD-10.1-PRERELEASE-amd64-20140907-r271243-memstick.img.xz and played a bit in LiveCD mode; it suspended and resumed correctly (screen and keyboard remained functional) twice in a row (at least).
There were spurious error messages from USB (lots of them) during the boot-up and especially when I tried shutdown -p now (graceful shutdown never arrived, had to press power button for 4 seconds):
usbd_setup_device_desc: getting device descriptor at addr 4 failed, USB_ERR_TIMEOUT usbd_req_re_enumerate: addr=4, set address failed! (USB_ERR_TIMEOUT, ignored)
Ethernet adapter is recognized properly, sound playback also works fine. WiFi and internal card reader are not supported.