Well, the music I am doing has a lot of sort of 'classic rock' guitars in it. Keith Richards'ey tones (well, sort of anyway) a bit of late 70's Eagles plus it has more recent tones such as Coldplay and even Robbie Williams. So no massive distorted stuff going on but a lot of (hopefully) meaty tones - plus quite a bit of cleanish tones as well.
I have suspected the 828's convertors but I don't know how big any difference will be compared to the preamp scenario. There IS a digital option for the SPL but unfortunately there is no way of trying that without buying it and having it fitted.