I really like CV when the boom balloon is up, because if you get 15 hits on the boom balloon you get an extra ball. This leads to some interesting strategy where you loft a ball up into the pops, or around the spin loop and against the boom balloon. The pop bumper action can send the ball into the Ring Master for Ring Master hits, or into the Menagerie for Menagerie hits, or down the right inlane/outlane area for the typical nudge fest that you must do to keep from draining.
I also like the 5 pops in TAF. They make for a lot of action, and the "Raise the Dead" mode where you try to get 4 hits on each pop bumper is a really cool mode.
Other than those, TZ's pop bumpers always have my heart in my throat as I try to determine if I'm gonna have to give the machine a last second nudge to try to save a left outlane or SDTM drain. A lot of people don't like the location of these pops, but no other set of pops give me the same "heart in the throat" nervous feeling as TZ's, and I like it.