I like a lot of the brands mentioned here but if you can only choose 1, how could you choose a brand that only has 5 or 6 varieties? Bucs are very good but I mostly smoke the Salsa or the Z. CAO's are good but I usually smoke the Brazilia or criollo.
With Fuente, I smoke hemingways in natural and maduro, 858's in maduro and SG, Chateau fuente sungrowns, Cuban belicoso, and Anejos. There's enough variety to keep me interested. If I could only smoke a small variety of cigars I'd get bored with cigars and probably quit.