I would have said yes till I saw Dimuth, who certainly deserves an opportunity. Upul has a great record and played a lot of cricket and will still probably have a role in the future but right now I would give Dimuth a try.
He's a top ODI opener and any day of the week I would pick him, but yes Stormy you're right Karunaratne deserves a chance.
Dimuth should have been picked by seniors are jel of his talent
Tharanga is the problem in Sri Lanka's ODI batting line up. Mahela should have continued as opener from 2009 when he showed he could be a match winner. Tharanga has played a few good knocks, but he's not a very good opener overall. I don't think he averages more than 30-31 against the top 7 teams with a strike rate of maybe 70-72. That's poor.
before comment please find correct average and strike rate values