And when I had the KN-7000, I was led to believe I could load KN2600 files into the 7000. Nope can't do it AT ALL! At least your T-4 will accept T-3 files that yes you may need to tweak, but at least you can load and tweak them. In fact no Technics keyboard is back wards compatible, while Yamaha files, for the most part are much more friendly with other Yamaha keyboards, up or down.
I have a Yamaha PSR-3000, and have hundreds of styles on a thumb drive, and maybe a thousand total that load instantly with no problems. True, if not made on a 3000 for the 3000, some tweaking may be needed, but I do have that opportunity to "arrange" styles. After some quick adjustments, I save the new edited style. Simple. No linking to ANY style is necessary.
Also when I record a song on a Yamaha it is saved as a midi file, where ANYONE can listen even if they don't have a keyboard. Where as Technics decided the default song save was a Technics file that is not the standard, and not easily shared. Ever try and record a song on a Technics and save as a midi? Talk about a nightmare!
Your T-3 and T-4 can record to wave with one button recording. The Music Finder on Yamaha PSR's are a quick and easy way to instantly call up a style for a song title, that a user has saved. You can instantly save your current setup to a registration, and it Will be saved for whenever you need it. No need to hit a set button, expand button, or any of those steps needed to save a registration on a Technics.
Sorry Audry, I disagree, the KN-7000 is a great keyboard, and I do miss it, but for me, Yamaha has the easier and correct OS
" Always Do Whatever's Next "