Yeah JC, you should give it a go. Give it 10 hours and you'll know if you like it or don't. Those early hours go fast, and as long as you're a little adventurous, you'll make great progress through that stage of the game. That's enough time to see a number of biomes, build a modest base and a Seamoth. I think if you like No man's Sky, Subnautica will be a good game to try. Especially as you already have it and for free!