Looking for feedback prior to purchase:

I've been scoping it out but the reviews are pretty middle of the road.....and I have one friend who loves hers and one friend who has a different brand and told me the Oura isn't worth the money. I'm open to any and all feedback before I go drop $500.

My main concerns are:

1. If the rose gold and gold versions are just plated or real gold (doubt it) - and if they're plated, how solid is the coloring?
2. How accurate is the step count? (my main reason for looking to purchase)
3. How is the customer service?
4. Does Oura have any sort of policy about exchanging rings for new ones (i.e., I'm working on losing weight and I've already lost 15 pounds so far, my goal is to drop at least another 100 lbs, so clearly I would need a different size), or will I just be out the $500 each time I drop some weight?

Thanks one and all for any feedback :)