Hello,
Well you should join the university more because of helplessness if your rank is not good enough to get an NIT. Still being a student I can share my personal experiences-
Advantage- the major advantage is the overall fees is less and and the lack of place for hangouts make it least distractable place.
Disadvantage- (1) The overall system is very convoluted, even to get issued a book from library you have to make multiple rounds for getting rental cards signed.
(2) There is no exposure, your life will be college to hostel that's it.
No place to hangout, even no facility to join extra courses and nothing.
(3) Teachers are not passionate though they may have knowledge. You can't expect anything from them.
(4) Coaching institutes for cat, gate are not well enough.
 
If you want to get placed in TCS then definitely you should join it.
To pursue computer engineering my personal advice is to get into some college with good locality so that you can enrol for courses outside college,  moreover for first 2 years in the college you will learn nothing worthwhile.
Just go through the courses you will learn in your four years of engineering in pantnagar at their official site and you will find most of the courses irrelevant. If you want to do less hard-work and enjoy hostel life and finally get placed in TCS then you should join it if you have bigger dreams then do look for other option.