Did anyone use the Heritage Card or Explorer Touring Guide? Look like it could save money for a couple, we will be there 3 weeks.
I used the Heritage card on my first trip and found that it saved me some money. It totally depends, though, on how many of the places you would be visiting anyway (and paying full admission for) as to whether it would be a cost savings for you. Check out the admission prices of the places you plan to visit and see how many of them you would have to visit it order to make it a better deal.
I used both an found them worthwhile. We skipped the Dublin Pass. But as the above poster said, it really depends on what you'll be doing. Add up the costs of all the places you plan to see that the card/guide cover and see if it's more than the card.
It only takes about 6 or 7 sites that are covered by the Heritage card to pay for it, especially if you visit mostly the higher priced sites. If you're going to be there for 3 weeks, you'll see that many for sure. Just do as the other postings suggest and check the current entry prices for each site. Another advantage for using the card is that you don't have to keep digging out cash or using a credit card.