From reading the Zoom website it seems that you must record onto the HD16 first, then you can drag and drop the files into Cubase for mixing purposes if you want to. Although it might slow down the process slightly (I sometimes like to be able to see what I'm recording on a computer screen as I'm doing it) it has the advantage that you don't need to have the unit connected to your PC to use it if you want to record an idea in a hurry.
Cubase LE is a good piece of software, it's probably good enough for most home recorders without the need to upgrade to the more expensive versions.
My only quibble with it is that compared to some other bundled software it doesn't come with much in the way of plug-ins and I don't think it has any loops to get you going, but I suspect the Zoom may include those so you'd be sorted.
I think the idea of having the faders linked to the DAW is good, it's much easier to use them than to turn dials and push faders with a mouse.
The only other point worth looking at is the quality of the audio interface. It records up to 16-bit/44.1kHz which is fine for CD quality, and again it's the most a home recordist would likely need.
Ultimately if you want to do more computer based recording then a dedicated interface from M-Audio, Presonus, Edirol etc with some bundled or free recording software may be a better option, providing you also have the disk space on your PC, but if you're looking for an all-in-one hard-disk based recording device, which has the added flexibility of doing the mixing in Cubase then it's looks good.
