I'd say that, although there is a tool for the Humax to do file transfers, the Toppy has somewhat better support (still third party, of course) for the Mac.
MPEG StreamClip includes file transfer functionality, talking directly to the Toppy via USB. You can even mark the in and out points while the file's still on the Toppy, mark where to cut out the adverts, and then download just the actual program, converting it on the fly to MPEG for DVD.
There's also an alternative tool called MacTF, which is AppleScript aware, and another one, for those with out-off-warranty boxes, which lets you read a Topfield hard drive that you've taken out of the PVR and connected directly to your Mac.
MacTF-EPG will grab the Radio Times EPG data, let you browse it on your Mac, and mark programs to record, then send the info to the Toppy.
Finally, ToFi is a firmware update tool for the Mac, so you can update to the latest firmware, without waiting for an OTA.
So, pretty much every aspect of using the box is covered from a Mac point of view.
Nigel.