Believe it or not, my experience is also based on the Siberia 200 (v1). I’ve never tried the V2, and it looks like they upgraded the headband for that model, which is good!
I owned a Siberia 200 for exactly one day before returning it in shame to the Best Buy. I have a stupidly big head, hahaha. The new Arctis lineup works well on my head. The Arctis Pro just fits even on the default tightness.