The first two that come to mind are EOS and STEEM. It would be a hard choice between the two of them and a lot of it would depend on the current price of each currency. I think if I was given this choice today though I would probably pick STEEM. I would then quickly convert that STEEM into Steem Power and I would then be able to start giving back to some of the groups that have been helpful to me in the past.
I would love to give a delegation to projects like musing and thesteemengine. I think they are great initiatives and deserve to be supported.
If the prices were flipped and EOS was at .88 and STEEM was at 5.71 I would then definitely pick EOS. With the recent release of Chintai, you now have the ability to lease out your EOS so that users can have more resources on the network. This is a great way of earning passive income just like delegating SP.
I have a lot of faith and good feelings about both of these cryptos. They both have a solid roadmap and good teams of people behind them working to make them better. There has been a lot of FUD about each of them, but I choose to look at the long term and given that I would have to hold for 5 years according to the original question, both of these fit that perfectly.