I don’t know if my 15″ laptop touch screen qualifies as large or not–but whenever my church lets me out of the FOH booth to play bass I’ll generally mix my own wedge running Editor on the laptop.
In general I’d say the slider controls on the iPad apps are more touch-friendly than the rotaries on Editor; I almost always end up tweaking with the touchpad on my laptop rather than the screen. Plus the iPad’s a lot easier to bring out in front of the wedges during rehearsal to quickly tweak as you can hear your changes.
Be aware as well, that if you’re thinking of a high-resolution display, that the Editor window cannot be resized or maximized–so you could end up needing to crank your monitor resolution way down to fill a decent portion of the screen with the Editor.
In short, unless you’re in a really hostile environment for WiFi or absolutely need feature access that can’t be done on the iPad apps (such as FX engines) I think you’d be better off with iPad.
