I have been to two seperate weddings abroad recently where friends decided to head off and get married they would do it all over again. Having been at both weddings I think I would do the same myself if the day ever arrives, here are a couple of my observations.
1. Having talked to the grooms it is far cheaper and you get more bang for your buck (depending on where you go), one wedding reception was in very upmarket 5 star beach resort in Portugal with a free bar all day I couldn't believe what it cost when told (very cheap) in comparison to how far the money would stretch in Ireland.
2. If you go down this route don't expect much in the way of presents from the people that make the effort/expense to actually travel to the wedding so a lot of the expense will come out of your own pocket. Having said that if you have a wedding in Ireland your going to have to foot some of the bill anyway as you won't get it all back in cash presents.
3. Get a good wedding planner very very important!!!
4. Give people LOTS of notice if your going to go abroad.
5. You may actually have to marry in Ireland in a registry office before you go and the church ceremony abroad will just be a blessing depending on the laws of the country you go to as happened my friends. This will in no one diminish the tears of joy shed on the day or make it any less special on the day
6. There is a great build up to the wedding as more than likely everyone gets to spend a few days together beforehand and gets to know each other as in most cases not all the family and friends from both sides of the bridal party will know each other. By the day of the wedding everyone is on a first name basis and the craic is great.
7. Invitations seem to be nightmare trying not to put noses out of joint and getting badgered into an invite for great aunt Bridie and the 2nd cousins that you haven't seen in 20 years when you only have room for a specific number of people. If you go abroad the people you most want at the wedding will make the effort to be there which makes it more enjoyable.
Whatever you decide good luck.