I have used just about everything at one time or another. I try new things from time to time but I always come back to Advanced Nutrients. For what it's worth, that's what I find gives me the best results consistently.
As far as your specific question about the base nutes goes, I would say if you like 2 part nutes to go with the Sensi Grow & Bloom. If you like 3 part nutes get the Grow, Micro and Bloom nutes they make. Connoisseur is awesome, but it's pricey. My advice is to test drive the cheaper stuff, see how you like that, and then upgrade if you want to.