If you are AB-ing, never forget to use the [ C ] button in between two tracks with the same name. This clears the Playback "cached" location - in this case the Playback Drive.
I've done my A-Bing by loading the tracks with the explorer button. I used a different naming scheme for EAC so there shouldn't be a cach issue, though that's a great tip abput the Clear button.
I also have not used the Playback Drive and I don't think it should make a difference for me. All tracks are ripped to a music folder on OS drive.
The difference between the two rippers is significant enough that I'll be reripping everying.....I'm pretty sure.