Napoli/Montero for Arenado

So, it's time to start chopping points from my roster in my crazy keeper league. I laid out my perfect-world keeper roster, and I have to cut from 7200 points to 4700. I have depth at catcher, with both Miguel Montero and Mike Napoli (and JP Arencibia, but he's def. not keeper-level), and cannot keep them both, so I've offered to trade one of them to another owner for Nolan Arenado, who I love, and who also will eventually fill my gaping hole at 3B (started Chipper there last year, and Mike Young, when he qualified [our positional eligibility is very strict, and can change every two weeks]). My real question now is, which one to trade?

They cost about the same in total points, though Napoli has about a 15% higher per-game average, with about 30 fewer games played. Montero gets a good amount of extra points for his defense, as we score for runners thrown out and catcher complete game wins (player must play entire game behind the plate and team wins). Napoli's season was extraordinary last year, and had he played the full set of games, he would have been one of the top scorers in the league (had he played 150 games and kept up the same ppg average he would have been behind only Miggy, Pedroia, Braun, Kemp, Ellsbury, Granderson, and Bautista), but I expect significant regression in BA, which will probably lead to at least some regression across the board. Also, will he still only play 4 times a week?

Montero, however, can easily maintain his stats from last year, and even possibly improve, which would make him again one of the most valuable catchers. Plus he's two years younger than Napoli.

So which one would you keep?