If your son’s first preference is CSE, then Amrita Bangalore clearly leads among the three, simply because CSE opens more doors in terms of placements, internships, and future-proof careers. Amrita is also NAAC A++ and has a strong reputation, especially for CSE. Category 2 is also manageable fee-wise compared to higher categories.

VIT Chennai is a decent campus, and their ECE program is solid, but Category 5 means much higher fees and very low chance of branch upgrade later. CSE at VIT Chennai would have been more competitive here — but ECE at that fee tier is not as strong a deal unless your son has a strong interest in core electronics.

Manipal Bangalore (MIT Bengaluru campus) is a newer campus. ECE there is still developing in terms of placements and faculty compared to the main Manipal campus. Unless your son strongly prefers Bangalore or is getting some advantage here like scholarships or internship access, it doesn't stand out above Amrita.

So, recommendation: Go with Amrita Bangalore CSE (Category 2). It balances a strong branch with a decent campus and better long-term potential in the tech industry. If your son is open to core electronics and you’re okay with the higher cost, VIT Chennai is fine, but still comes second to CSE at Amrita.

All the best!