Definitely Pro! It’s the cheaper option. No need to mention the 32bit as you already mentioned it. I have both and if I had to buy one of them, it would definitely be the Pro option.

I have both the Go IIs (which I loved) and the Pros, (which I preordered sight unseen because I was so impressed with the Go IIs). The extras you get with the Pros are absolutely worth it. The Lavs, the magnetic mounts, the whole shebang. Plus they have a chunk more recording time available, and the 32bit is not to be underestimated. They'll last you a very long time.

Also to note - if you're ever looking for an upgrade, I have some Sanken Co's IId mics which work very well with any of these and the combo has never let me down.