Well, no blind suggestions and verdicts, it depends on you what you choose. Let me make some points about UIET which may help you in your decision.
- First thing you will get is a brand name associated with you choosing any of them and Panjab University is way bigger brand than any other university in Punjab.
- Second thing is exposure(city and life), up to you to choose between Chandigarh and Patiala(no comparison here)
- Alumni connection: (most important for placements): Thapar is a winner here as they are established in 1956, way before 2002 of UIET.
- MHRD Ranking: Thapar is 26th so better without any doubt(in engineering colleges). PU is 12th and TU is 75th in University ranking.
- Placements: No idea about TU but every eligible CS and IT student get placed in UIET (min CTC is 375000 here)
- Infrastructure: Never visited TU, PU has one of the best campus in Northern India.
- FACULTY: No doubt in first year you will suffer, from 2nd year onwards you will get the best(and I mean it the best)