QUOTE(xboxmods2977 @ Mar 29 2012, 03:41 AM)

I have heard that there was a length limit to IDE cables of like 3 feet or something, but other than that, there is nothing special about the lengths, or connector spacing. Standard cable length is about 18 inch (I don't know how many centimeters that is), so I would stick as close to that length as possible. As far as having a 3 device IDE, it is a bad idea. You are just asking for problems there.
No there are no problems with this, it is a relais between the HDDs. i can switch between them so that one becomes power the other not.