Hello Ganesh,

CET pattern is more or less predictable, unlike CAT. So most of the test series follow the pattern. But the CET varies with difficulty levels with the cutoffs for JB varying from 120 to 165. So it is ideal that one should write mocks of varying difficulty levels. Due to this every year students claim different test series are good based on whose difficulty level of papers is closer to actual exam. This varies every year and the opinion may vary before and after the exam.
Now there are mocks given by the big classes like Time, CL, and IMS and there are mocks given by smaller classes like mine - Quoin Academy. Each one would claim that their test series is best and must have prepared the mocks after proper research. I usually advise students that if you plan to join two mock test series, you can join one from the big three classes where you will get the ranks, and one from a smaller institute which can give you individual guidance with regards to your planning and strategy for the tests.
Hope this answers your query.