I haven't got IO, but my understanding is that it's very much akin to the "multi" patches that you would get on a synthesizer. That is, one particular patch will give you various instruments spread over different parts of the keyboard. You can use the modulation wheel to dial in different layers, so (for example) the initial patch might be strings, but turning up the mod wheel will add brass on top of that.

You can find some good examples of what IO sound like on YouTube.

The ensemble would be on a single track, but you'd likely want to play it yourself, rather than expect BiaB to perform something that would match well.

Most of the textures in IO seem to be the big, cinematic sorts of sounds, which are generally not the sorts of things you'd be adding on to a pop song. I'm not sold on it being a good match for BiaB - I suspect that in general GPO or JABB would be more useful.

I've got the Mixcraft demo loaded on my machine. It's a slick program, with some nice presets. In particular, the MIDI notation editor seems nice (Reaper only has piano roll mode), and the Acoustica MIDI instruments that come with it seem very usable. BiaB doesn't seem to like the Acoustica VSTi.

On the downside, the loops that come with Mixcraft (which is what initially got my attention) have an inordinate amount of useless filler sound effects, and not enough usable material.

One thing that Reaper lacks is a display of a loop's key, which seems a baffling omission to me. So if you work with loops, Mixcraft is likely a better match for you.

On the other hand, Reaper seems to have a better integrated wave editor. Mixcraft doesn't seem to be designed for the sort of microscopic editing that I like to do.

Again, it's all about finding a tool that matches your workflow. It's all digital, so one DAW isn't going to sound better than another.

-- David Cuny
My virtual singer development blog

Vocal control, you say. Never heard of it. Is that some kind of ProTools thing?