Quanchi, this thread hits quite close to home for me...
I myself, had my first dating experience (with a guy) recently; I am 20, and he 27. We had met previously but didn't talk beyond pleasantries, but we began to talk through Facebook after I came out. We decided to go for coffee at a cafe in the mountains near where I live. Things went great and we ended up extending the first date with a walk at a trail near the cafe, and even went to a look out after that. I was getting mixed signals though; one minute he would be affectionate (holding hands on the walk, kissing at the lookout [my first gay kiss!!

]), but then he would kind of, distance himself? I guess? He expressed concern about dating someone so young...Over the next week and a half, we went out 3 more times. My confidence was skyrocketing and I noticed I wasn't afraid to do things like hold hands with a guy in public etc. It felt great, and I chose to focus on that, and his affections, as opposed to his obvious reservations.
I'm far too naive and romantic, and ended up getting more invested than I should have. He had expressed his concerns to me more than once, and despite us talking about it, there was no way I was going to change his mind. I wish I had known that beforehand. I wish I stopped myself from getting too invested with someone who wouldn't allow himself to do the same. I wish I hadn't fooled myself into believing I was more mature than the average 20 year old, and I wish I didn't waste my time trying to convince
him of that.
Anyway, I'm starting to rant and get too personal, but my point is this; don't make the same mistake I did. Don't let yourself get too involved if the other person has expressed doubts. Though from the OP, it sounds like you know this already. '
We plan on being friends and left the door open if he ever changed his mind' ---- this is a good idea, and looking back, it's the route I wish I had taken.
I think age-gap relationships can work. I, for one, have no issue with any age gap at all. As long as there's a connection and both parties are comfortable with it, there's no reason for it not to work. It's certainly an area where one must tread carefully though; lesson most definitely learned.