[Fish Sandwich]

Patranger all the way for me. The thing is though, I think this question is less about cops and criminals, and more about new-school vs. old-school. I'm not sure how intentional any of this was on Toei's part, but if you look at the Lupinrangers, they've got these really slick, cool suits that look like a lot of relatively recent Sentai (the hat-visors in particular remind of a lot of Timeranger), and similarly their robot has that same generic face that most Sentai robots started having some time around the nineties. Compare this to Patranger's suits, with their less dynamic shapes and heavy use of white (which again, used to be a bit more common), and their robot, which has a very classic Super Robot look to it. Even looking at the actual show, the Patrangers sole motivation seems to just be "we're cops!", while the Lupinrangers get a more elaborate goal.

At least, that's my take on it before actually seeing the show. Honestly I think one of the coolest things about Lupinranger VS Patranger so far is how, despite the Lupinrangers getting top billing, neither seems to be the "true" heroes, so hopefully we're all still discussing this even as the show's well into its run.