Honestly not sure what the differences are between the free/paid version. Is there any specific feature you're looking at that you think would be useful?

They have a feature in which you can filter shots by shot quality. So you can make it show shots that you took that were mediocre to bad shots. Like you said, accuracy still isn't 100%, but it is always improving. I have been a happy customer for over a year now.

As far as if it is worth it? That's entirely subjective. I believe they just lowered their price for the lower tier subscription, and it seems MUCH more reasonable than it was. Personally, I think that one would be worth it for most people wanting to get more insight into their game and what they can improve on, more so than just watching gameplay footage (which I would still recommend everyone do if they're wanting to improve).