RE:If I had $500...what sw rod should I buy?
All depends on what your target fishery is... for SWFF I waited a long time to get there but picked up a Sage 9ft 9wt 3-pc travel RPLXi last year. It's the best casting SW rod I've ever owned. It's not a broomstick by any stretch, but it is certainly tuned into casting a 9wt fly line line nothing else I've tried.
A trout and steelhead / salmon rod would be different, as well as tarpon, etc.
What's the application?