I resisted ,using them for a long time until I got the BK9 with its Jump/Mark buttons. I edit them and can play along doing the keyboard part as ,I would with a band. And I'm in full control of the arrangement as I would be using a Style. Lots of fun.
There's a drummer here who plays with a long established band but also does solo gigs using Midi files. He plays drums and sings over them. Very creative.