Considering upgrading my 2020 HW3 Model S

Hey all, as the title said I’m considering upgrading from my current Model S. I purchased FSD outright. I was originally planning to wait for the next hardware release before upgrading but as they are discontinuing the S, I feel like I need to act.

A few questions for folks who have made similar upgrades:

Going from HW3 with no interior camera to HW4 with interior camera - has anyone who made the change regretted it? Right now on long highway trips especially with open roads I’ll often find myself multitasking and didn’t know how the newer systems with interior cameras react to that.

Having previously purchased FSD outright, it was my understanding that Teslas intention was to give FSD to me on a new car for free since HW3 isn’t capable of delivering what was promised. The current model S has FSD built in to the sales price automatically. I inquired through a representative and they bumped my trade in value estimate up about 1800 bucks which seems a little low. Has anyone traded in their HW3 FSD cars and figured out how to truly get a price benefit?

Thanks in advance.