Buy and try my friend! The only thing, and I am sure its been said many times with Valheim is, "DO NOT RUSH IT!" Sit down explore carefully and learn the system and the Biomes one at a time and your golden as a solo OR as a co op.

In co op play the mobs get tougher the more folks are online and in thier area BUT not linearly so 2x players doesn't make for 2x the hit point son the Mobs so in a sense Co op players have it easier IF they can combine on foes effectively. But if their co-ordination sux then they fight 20% or so tougher foes per player so again if the co op is unprepared or taking it too fast they are worse off.

Lotsa fun here as long as you are prepared to take the occasional death as you learn which should be normal for the genre

(NB also beware the deathsquito near the shores once you start sailing! Its an exception that thing will come after you across Biome borders more than most!)