See , I would prefer IIIT Sri City over IIIT Trichy. There are many reasons. First IIIT Sri City is now having a permanent campus of its own. Second , the coding culture of Sri City is better than that of Trichy. As you know IIIT Hyderabad is the governing body for Sri City. And NIT Trichy for IIIT Trichy. So it's obvious that CSE will be good in IIIT Sri City. 

Also the average package at Sri City is 8+lakh package. Also if you are good in coding then you might also get around 20+ lakh package. 

So I would suggest to go for IIIT Sri City.