I am a catking Student so Ill definitely recommed the same but you can also go with IMS as well !!! 

these both are amazing 

CatKing for sure! Their tracker and graphs help you a lot to actually track your progress which was extremely useful for me

CATking is best !!!! 

CATKing yiu can try their RCs are very much at CAT Level , I found many talking about catking Mocks  

TIME , CATKing , IMS 

I belive inke bhar mat jana