What you buy depends on what you want out of your simulation experience. I happen to like "closest-to-real" equipment to what I'm flying.
I've been using Thrustmaster since the early '90s. Currently, I'm using the Thrustmaster AVA base with the latest F-16 stick, but the old Cougar F-18 stick. You swap them out on the same base. I've been flying the F-16 for decades, but the last 5 months have switched to the F-18 and have the F-18 stick mounted. It only takes seconds to swap the sticks out. I'm also using the TM Viper TQS (Throttle Quadrant System - has a small panel with knobs and switches on it), but its quality has been questionable. In addition, flying a two engine aircraft with only one throttle is a little awkward, but not a real problem for me.
The generic sticks and throttles have the advantage of having more buttons on them to program.