UPCAT

I have to say that the crowd and teachers are average and there are no extracurricular activities since most private colleges of IPU have small campuses. But there are a few advantages which people ignore-
GGSIPU has been the life saver of Delhi students. Without its existence, we would have no where to go and I mean it! It is the only university in Delhi apart from DTU having reservations for Delhiites. (Considering stiff competition in DU & IITs).
Yes, it does spoil our new year celebrations & we have to pay high fee but then the lenient checking of our marksheet helps us in improving our graduation marks! (Just fill pages with decent content and you score 70+). Only university in Delhi offering professional courses like B.Tech, BCA BBA B.J. M. C. and courses in medical sciences, with compulsory internship projects. Clean infrastructure with AC rooms, although small. (In private institutes)
Geographically covered colleges in almost every region of Delhi-Kapashera, Hamidpur, Tughlakabad, Rithala and the list goes on. Even if you don't get a decent rank in CET entrance, there is an open management quota system to grab a seat in any private college. (If you have extra money in your pockets). This assures your admission anyway!
There are pros and cons of every university. And I'm grateful that this university exists in Delhi to fill the demand and supply gap in the city (more students but less seats), unlike DU.
UPTU
I will not recommend you to study in any UPTU colleges. Colleges of UP that comes under UPTU (Now AKTU) has no or very less value outside UP. That's why many call UPTU as Ut-Patang Technical University. These colleges follow very old syllabus and infrastructure and facilities. My advise would be not to go in any college of UPTU unless you are getting very top notch college like the HBTI. Best of luck.