I finally tried out Resolve the other day. I spent 2 days trying to isolate a couple doing their first dance from the background so that they were the only ones in color. Motion tracking works pretty good, but of course can't keep up with the complex mask shapes required to make 2 people spin around each other, so it still required an extensive amount of manual keyframing (so much so I had to scrap the scene because I couldn't deliver it on time). I really like its keyframing layout though, auto keyframes each time I make an adjustment, the mask points are overlaid right onto the preview window instead of being in a separate window, and motion tracking does a great job of filling in the blanks between keyframes so you only have to manually keyframe every 5-10 frames. GPU acceleration seemed to work great, I didn't see a single bit of stutter during playback (though that isn't the most demanding effect to try) and the render was lighting quick.

What I don't like... Vegas is no saint here, but Resolve crashed on me several times throughout the process. Also, another complaint I commonly hear about Vegas, the render was unusable. It had glitchy frames, almost like a misplaced frame in the beginning. I'll upload the (incomlete, I never finished keyframing) clip so you can see what I mean. The UI is horrible. Hovering your mouse over something doesn't tell you what it is, I often found myself having to consult instructions for simple tasks that I should have been able to figure out on my own.

My question, I have the BCC stuff that comes with Vegas Pro 14 Suite, which comes with Mocha (though only on limited effects, apparently there are ways to use it outside of just the witness protection/etc plugins that use it). Is there a way for me to achieve this effect within Vegas Pro? Hopefully without adding complexity to the process of creating the effect? If not, are there options for Vegas that I can buy to do it?

I never finished this, so it looks terrible.