If you are going Sunday June 5th, the flash pass is very likely to be worth it.  Personally, I am choosing Gold over Platinum because riding rides twice in a row really angers other people waiting on line. 
  
Go to yelp.com and read the reviews for Six Flags Magic Mountain.  They are very informative. 
I thought the gold only cuts wait by 50 percent though .  I can care less who gets mad I paid for it so dnt get upset.