I've tried both. I'm disappointed with Cocoon.IO since it doesn't support many plugins + It has many unused permissions that makes our apps suspicious & bloatware. 
I'd go with IntelXDK if I were you. Developers there are experts in compiling HTML5 apps. All cordova plugins are compatible there + no noticeable bloatware.
Yeah as  Rasputin said, the only downside is the apk file size.
Rasputin said, the only downside is the apk file size.
BTW IntelXDK is way faster now compared back then when Cocoon.IO was said to be faster.