Hi Frank,
mainly because OMB is an all in one package.
Realtime Arranger
Style Editor
Sequencer
Arranger etc

I basically flick from one function to the other. If a styles not working , I check out why in the stylemaker page fix it and test it.
Arranger page, I can type in a chord progression and put in the style parts ( from up to 10 different styles) handy for auditioning styles for songs without worrying about hitting wrong notes or chords. In short I can concentrate on what it actually sounds like. ( Also use Busker Software for this)
Also realized I can scan sheet music and use it with omb in realtime ie it scrolls as you play styles . Haven't had much time to spend on that, but it intersts me, as I read, I can't play by ear.

Livestyler sort of "looks" more proffessional than omb. I did try it originally about a year ago, but te version I had , couldn't play piano arpeggio's correctly ie I had some piano styles from my 9000pro and it just didn't play them right wheras OMB did. I had other sorts of styles playing okay, but not the ones I wanted. By that stage I got so involved with OMB, I never went back to Live Styler. Suppose I should give it another go oneday, especially since we're up to vers 8.

best wishes
Rikki