[Marc Chapuis]"Is it capable of capturing in HQ mode."
I honestly don't know. What I do know is that you can't record under/overcranked footage to the hard drive because the data rate is too high for the device's USB 2.0 interface. So, maybe the specification you read is correct and that the hard drive is only good for recording in SP mode, which is basically HDV format. The other thing is that you have to upgrade to the latest EX firmware, which is v.1.11, otherwise you won't be able to use the drive. The firmware upgrade will also allow the use of the 32 Gbyte SxS Pro cards.
NOTE: If your EX3 was shipped after the first half of August then it's supposed to already have the latest firmware.
That got me worried as I have one on order!! but here's from a press release:
'Also shown is the PHU-60K hard-disk unit designed for use with XDCAM EX camcorders - this is a 1.8-inch, 60 GB external storage unit with an USB 2.0 interface. Recording times of 200 minutes in 35 Mbps HQ (high-quality) mode and 260 minutes in 25 Mbps SP (standard play) mode. When attached to a camcorder, the hard-disk unit functions just like an SxS PRO card, with thumbnail views available on the LCD panel of the PMW-EX1 or PMW-EX3 camcorders or PMW-EX30 deck'.