If I want a huge amount of variety in a tune, I simply use several styles that have been programmed to be complimentary to one another...plus, I reprogram all my intros to do the work of extra variations and/or have them act as act as break fills or perhaps 8 bars (or whatever number I want) of the style without certain parts...just have bass and drums for example...I can still play chords over it and leave it at any time by pressing a Main Variation button (or fill-in button) or I can let it complete its cycle and return on its own.
I've been editing styles ever since that feature was first included on an arranger...I rarely, if ever, use an unedited factory style.
If using midi files was more beneficial to my way of playing, then I'd be using them, no problem; and, I wouldn't feel I'd need to justify using them.
That's how I feel about using styles...they just work perfectly for my needs and my style of playing.
There's no RIGHT or WRONG way...there is just the BEST way (including using BOTH ) for your personal needs.
Ian
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Yamaha Tyros4, Yamaha MS-60S Powered Monitors(2), Yamaha CS-01, Yamaha TQ-5, Yamaha PSR-S775.