IM with travlin'easy on this. Heck his post near mirrors some of the stuff I was gonna post ( that I dint ":P )

LCD...only issue here is after XX amount of years, backlight could go out. Any other problems would be related to direct damage to the board.

Disc drives, I agree no reason to go with a floppy drive. Unless you want a retro something, or if the floppy drive is only the back up for a memory card. Floppy drives are not total horror, even with the drive on your PSR550 being an exact example of how not to implement one. I happen to like the 550 ( past its silly dependence of the floppy and crap headphone jack ), so IM guessing some of your fears of floppy drives is a direct result of your time with the 550.

Jacks...Yamaha jacks are workable when they give you enough of them. This being my only real gripe, you have to spend near ( speaking in generals ) a grand just to get left/right 1/4 inch independent outputs with new Yamaha boards. Get past that your dealing with jacks that could be mounted better, could be balanced better, and could offer lower noise...but still do their fundamental job. This is the weakest link of Yamaha boards for me, as is a general lacking of effect options when contrasted to what Yamaha offered a decade ago ( on some boards/series ).

Buttons...what of them, they do their job " Only thing button related I happen to dislike on the new Yamaha's, the jog wheels feel like complete cheep crap. They work...just subjectively speaking BAH.

If you don't need the arranger features of the current Yamaha's, I would hint big time that you open up some other options. If you do NEED the arranger features...well then......Yamaha "