I'v been upgraded once to Premium on Virgin Atlantic flying back from LA, but the Vegas flights get so booked up that there's never any chance of an upgrade - they only allocate 2 seats for First, Premium and even Economy on the Vegas flights for people exchanging miles, and then because the rules for the scheme say there is always an allocation on every flight - hence the early booking!

As for chips - I had no trouble at McCarren bringing back chips last year, but they did pull me over to look at my bag because of the brass chip that I picked up from the Stardust because it was a 3 inch metal disk that the XRay couldn;t identify. Perhaps they are getting more used to people with lots of regular chips

Jason