It's what you make of it , regards to research do you think you'll get to publish and co-author a paper? Research is more of a lab based environment where you get to find and piece patterns or data points together and find out why something is the way it is. Where as in an internship you will be able to work on something more tangible per se.

It's really up to you ! Can't go wrong with either , I've seen ppl do either research internships and it has not hurt them in any way.

However, I wud say that internships definitely weigh more since there are return offers ... but depends on what the internship is and again what you want to do in your career as a developer ...

I decided to do research Junior Yr summer , v fun , then again depends on your team , your interest and what you make of it !

All in all, it's not a bad idea , research, Make the best out of it, find out what u like to do and what u don't like. Build connections with professors and the other members on the team who obviously have colleagues in the industry !!