You're one of the few people on here to have actually rated themselves. I'm curious to know if your idea of a 5.0 is consistent with the level of a So. Cal. 5.0.
Do you have a similar rating system like us? Here your dynamic rating changes after every match you play.
The Dutch rating system conforms to the ITF rating system and is not the same, numbers-wise, to the US. According to the ITF rating conversion chart, a Cat 5 in the Netherlands is equivalent to a 4.0 in US NTRP rating, and a 5.0 NTRP rating is a 3 in the Dutch (and ITF) rating.
The dynamic ranking is similar though.
Californians seems to rate quite hard. There is a bit more "grade inflation" in some of the other states.