Whatever the reason, Technics got it right as far as the operating system goes. Yamaha's system is a nightmare. When I bought my T4 I was led to believe that all my Tyros 3 sets would play on the T4. O.K. so the preset T3 styles do play when they can be matched on the T4, otherwise the T4 will compromise with the nearest style thus making my set sound completely different, sometimes even 'rubbish' for that particular song.
Third Party styles are a NO! NO! in the T4 and cannot be played until linked with the relevant on-board styles. e.g. T3 had a lovely Jazz Orch Ballad on it, which was tweaked and put out as a Jazz Ballad on the T4. It isn't anything like the T3's so in order for me to play my ballads saved to this style, I have to link it to the Swing & Jazz on the T4 before it will play. Another thing Yamaha have done, is to add several new voices and styles but it has upset the alphabetical/
numerical listing, so now we're having to delete and rename/number our saved sets as well. And with absolutely everything you do, you must remember to first press the Registration Button, the Style, Voice or Song Button before you can get any life out of it, simply because it saves to these separate positions.
Technics on the other hand, allows you to setup and save everything all in one go and gives you three load choices, all simple and un-complicated. It doesn't matter whether they are presets or third party.
The T4 is all button pushing and very little play for me at the moment. Thank goodness I kept my KN7000. At least I can play it for awhile and get rid of my frustration with the T4.