Both are good. Eyeo can be a little more Data Visualization if that interests you. Inst-Int is another one that is put on by the same people as Eyeo but doesn't sell out as quickly. Eyeo's venue is very nice, great screens and no bad seats.
I've only been to Resonate once (2013 I believe). I think it has changed venues since. I liked the content better and really like the recent options of the week long workshops. For me, if travel wasn't a variable, I would choose Resonate.