Battery that lasts just over two days has been the biggest impact for me (coming from Series 4). The extra button is cool for hikes because depending on how you set it up it can help going back the way you came (track back). I haven’t used for diving but tested the depth meter and that was cool. The benefits a squarely in the “nice to have” category.

I'm really curious to see what happens this year with the Ultra- will we get a refresh already, or will it take a little longer? I like mine, but wouldn't pay full price for it. If you can find a used one for less that would be ideal. If you don't use sleep tracking, don't swim much, and aren't doing any extreme hiking, don't bother spending the extra.