Monarch Airlines; Flight Delay compensation

Advise wanted please. Under the new rules passed by the EU you are now entitled for compensation for flight delays over 3 hours provided the flights are between two EU countries. This can be backdated to 2005. In October 2011 we experienced a 5 hour plus delay on on our outbound journey to the Canary Islands and a three and a half delay on the return journey.The reason for the delay was technical difficulties- not weather or strikes. This was on a Monarch Package holiday. We tried to claim compensation from Monarch in November 2011 but they declined saying no laws had been passed for any flight delay compensation.All we got was a £10 food voucher each on the outbound journey and £5 each on the return flight. Following the recent ruling by the EU our reading of this rule is we should be allowed 400 euros per person per flight compensation, A total of 1200 Euros. Before trying to claim from Monarch ( I am sure they will try and get out of it) can anyone confirm we are correct in our calculation of the amount we are going to try and claim. Thank you