Interesting, past TT member and fan. Due to health we sold our RV and TT membership this year. We would not have been able to full time for 13 years without TT. Have used Good Sam, KOA, Passport, City, National, etc etc. I never recommend parks because what works for me may not work for you. 20 years ago when I first joined TT, all the parks were in better shape - but so was I!
Really have to do your homework and figure out what you want, ask lots of folks about their experiences. Guess we got good at "the system" we loved the NW and rarely had an issue getting in any of the parks. Once we went into overflow and within the hour, ranger came over with an assigned site for us.
Whatever you do, enjoy! It'll all make for good memories to discuss once you have to hang up the keys. (Howdy BnB)