I have had a DMR-HS2 now for a fortnight. There is a minimal amount of whistle from the hard drive but it certainly is not excessive. in fact the hard drive noise is less than that of my sky+ box or the Tivo recorder. perhaps if Automan isviewing these forums he might like to pass his opinion as he is well versed with all of these hard drive recorders
I have the advantage of having my unit in a cabinet with glass doors underneath the television. however with the doors open and the television turned off, my machine, which is currently dubbing from ram to hdd,can be heard from across the living room if everything else is in total silence.
I dont know if you have any other experience with hard disc recorders, but it is a feature of their operation that you can hear low pitch noise.
The HS2 has no still frame advance,this was very useful for doing accurate edits.It also doesn't have the same picture adjustment (colour,brightness,contrast etc) as the DMR-E20,also I think the DMR-E20 was much classier with it's aluminium front panel,the HS2 looks cheaper.
Rob: You can do frame accurate editing on the HS2. When in partial erase for example, press scan fwd until you get to approximately the edit position. Hit pause, then fwd or reverse to step through one frame at a time. I've found you can get really accurate edits this way.