Both of my systems use rounded cables from SVC, and I don't seem to be having the big problems with data loss that that article seems to forecast. I've got 4 drives (2HDD, 2 optical) in my main system - 2 rounded cables total, I think the one is 18" the other 24", or else they're both just 18", I don't remember. My secondary system has 3 hard drives, a ZIP drive, and a DVD-RW drive. 2 drives are on short, single device cables (RAID array), 1 drive is on a dual-device cable, and the ZIP and DVD-RW are on another 24" cable together. So I've got a total of...6 rounded cables to push data through. Can't say I've had any problems with them.
From this you can see that bundling up all your cables into a neat round cable does not improve signal transfer along the lines. By doing this you put signal lines next to one another as opposed to having them separated by an earth line. This means that your signals are interfered by all the other signals to quite a large extent.
But they are twisted pairs...I was under the impression that this helps to reduce interference.