All has been said but I'll mention Streets of Willow again.
That track's a 250's dream come true
In all honesty if I did WSIR and Streets all year I'd be really happy. WSIR teaches you riding really high speeds and Streets is technical as hell and makes you WORK.
Buttonwillow will always have a special place in my heart though. Eventhough I destroyed my bike there
I'm yet to check out Chuck. But it will happen very soon.