You can get MGMAT cats for 26$ by getting one of the 8 strategy guides. Spend 25 more bucks and you get the GMATClub tests
as well. Apart from that if you are starting to prepare, then you should go for MGMAT as GMATClub quant and verbal both are like for advanced test takers, they are quite tough and might demotivate you when taken at the beginning of your preparation. You can get GC tests at a later stage of your preparation. By then try to be more active in the forum, participate and help others, and get 25 kudos. You can GC Tests for free by redeeming kudos.
KUDOS - if my post has helped you.