I Can’t Harness The Right Harness

There are soooo many darn harnesses out there with so many sizes and designs, it makes it pretty difficult to choose the right one especially for a greenie like me.
The harness is such a critical accessory that you want to make sure you get the right one for your application. My problem is, I have no idea which one to get.
2" or 3"? Sewn or latched? 5 point or 4? Which brand? I’ve heard a lot of good about Pro Armor but still can’t decide which configuration to get.

I want something that’s easy to get in and out of and will work for my 8 year old boy and with my stock seats.

Thanks for any advise