Hey,
I took a test 2 years back at the Chandigarh center in Sec 34, and to be honest it is pretty tight and a little claustrophobic. to make matters worse, there was no facility for the toilet at the time. As the center was in the basement, i was taken upstairs and then to the next showroom to use the services. Half way there, i realized i would be late for the exam and rushed back without using the services, and that was probably the worst decision i made. Throughout my verbal section i was struggling. As a result my score was 48Q and 25V

(Although the low score was not entirely because of that, but i do remember wishing the test could just get over.lol)
Anyways, i am writing it again within a weeks time at the same center, so hope things are better now.
Delhi Center, is good! Been there and heard a lot of good reviews about the one next to green park metro station (HauzKhas/Yusuf sarai area)