What are the best GMAT Prep books to use?

Hello, I am planning on taking my GMAT next year over the summer and I am a bit confused as to which study books to buy. I was initially going to purchase the GMAT Official Guide 2018 Bundle: Books + Online https://www.amazon.com/dp/1119396174/ref=cm_sw_r_cp_api_80eeAbEKKABB8 From Amazon but the mor...