It will be interesting to see how important UEFA view these play offs.
Do you:
(a) Appoint referees from the lower third of the Elite group and say "here is your chance" or
(b) follow the Champions League example (where play offs are seen as v important) and appoint Cakir, Brych, Kuipers etc?
I would hope given the importance of the matches for the teams involved that the likes of Cakir, Brych, Kuipers etc will be used.
Hungary v Romania if it happened would need a very strong referee, it is a bit of a bloodbath at best! Sadly if it does happen I fear it will be remembered for which set of ultras managed to boo the loudest during the opposing anthems, which set of ultras won the street battle before and after the game & possibly even during it and how big the fines are for each country for the racism!! The pyros would be awesome though! If you go onto youtube and search for either anthem at a game between the 2, you will see how hostile the atmosphere is. I wish it would stop and I can imagine both FAs are hoping it doesn't happen. I would certainly go but wouldn't even wear my Hungary scarf even in the relative safety of the press box! Hungary however haven't won in Bulgaria for 53 years and Iceland will be no push over for Romania especially away from home. The Iceland fans are amazing!
Also a potential for Northern Ireland to play the Republic of Ireland (again not counting chickens...). It would be very loud! That would need a strong referee as well but I don't think it would be a hostile game.