They have the same meaning, lromao. I think, it,mostly, is being used אין בעד מה

In my opinion, you can use either one. I'm not sure that one is more common the other as both sound very natural to me. I would say that nowadays many people reply בכיף or בשמחה too (their meaning is different, but the intention could be the same - "I was pleased to do something for you"). An older phrase that can be used is בחפץ לב (which I like the most!).