CS in bits or Vit ,which is more valuable ?
As both the colleges are very good and most demanding also after top NITs and IITs, but I would suggest you to consider BITs first then VIT (main campus).
To know about both of the colleges and their reviews, you can go through below links -
Birla Institute of Technology and Science, Pilani
BITs Reviews
VIT University, Vellore
VIT Reviews
Hope this helps!!!