Highly depends on what you are looking for. I study at VIT Vellore and am from Bangalore, so I have a fair idea about RVCE.
Location: RV wins here, right in the silicon valley of India, great oppurtunity for internships/workshops/seminars.
Exposure: VIT takes this one. VIT (particularly Vellore campus) has many clubs and chapters pertaining to about any field you might be interested in, be it dramatics, debate, quizzing, music, fine arts and what not. Moreover students from every nook and corner of the country study here, I was surprised when I found out that in my batch of 61 mech. engineering freshers, I was the only one from Karnataka and the rest were from nearly every other state in India. Such is the diversity here.
Campus: VIT Vellore again. Just google both colleges and you will get the idea.
Placements: For core branches like mech/civil, its about the same. RV has better placements for CS, although I know plenty of seniors at VIT who landed up in core development positions. RV has a much lesser undergrad population so that is really helpful while placements as it tones down the competition.