I am not sure about the other two questions, but as far as the first one goes, the Lexmarks have drainage holes, and the IBM Ms generally do not (I don't know of any that do, but I can be wrong). I am not sure what "captive leads" are, so I can't help you there. Lastly, it is generally regarded as a myth around here that the Lexmark Ms were of any lower quality than the IBMs.