My bad. Sorry. I should have been more clear. Yes, /r will take longer but that is because it is way more thorough and IMO, if the condition of the disk is in question, reason enough to be patient and let it run through completion.
You might want to make sure Quick Removal is enabled for those devices. When enabled, it can degrade performance a little, but it ensures the OS writes all the data to the drive before it moves on to other tasks instead of temporarily stuffing the data into a buffer or cache. When enabled, it (at least in theory) lets you disconnect the external drive almost immediately after you perform a save (or close) operation.
