When coming here on a one way ticket at the start of my contract, I was stopped at Heathrow check in and had to provide evidence of employment (QP contract) and the downloaded copy of visa that I had printed. At Immigration this end, they processed my visa in a matter of minutes, all I had was a contract and a very fuzzy printout of the visa. Because they already have your details in the system, they process you by scanning your passport. It was no problem for me, except that the airline wanted to make sure I wouldn't be refused entry as they get fined. This was less than a year ago with a British passport. May be differesnt for other passports. One thing I can say is that the Immigration guys at Doha were very professional and knew what they were doing. All the best, JJ