I not only use real Amiga drives in Winuae, I have also used Winuae to format, prep and install the system and software on drives for my Amigas. I have used USB, Firewire and SCSI external cases. You need at least OS3.5 for the harddisk toolkit to work right. You also need a fairly recent version of Winuae. I recently took an old 3.2 gb laptop hard drive, put it in a USB case, started Winuae from a command window with the [disable saftey check] bypass switch so it would regognize the drive, partitioned it and formated it in OS 3.5,restarted winuae with the now RDB Amiga drive as the hard disk and 3.1 install adfs loaded int the virtual floppy drives, installed system 3.1,ejected the virtual floppies, rebooted to the Amiga drive with a fresh 3.1 install to check things out and then added a couple of Winaue hdf volumes to the hard drive list, rebooted again and copied a lot of software onto the hard drive from the virtual volumes and then installed it in my A4000D and booted it. It is a lot less tedious than swapping floppies. There is also a function in Winuae to directly image Amiga drives and this is fantastic for backing up Amiga drives and then you can use these images to set up a winuae emulation of your real Amiga.