I lived in Portland a million years ago, before I started racing, so I had to look up the series. It looks like a blast! I'll put it on the bucket list if I'm ever back in the States, and near enough, in the summer.
The fun thing is the race usually has a good crowd watching and cheering, so a great vibe. The crowd is mostly family, friends and racers in other categories but many folks bring a picnic out and enjoy an evening of bike racing.