The only catch to the Rome math: if you get into a situation where there truly are no good hotel rooms available in Rome for under $500, your desired Marriott award is probably not available.

I always assumed the catalog was targeted specifically for people who spend 250-300 nights in a hotel. They have oodles of points and little desire to redeem them for yet more nights in hotels. (These same people also likely have oodles of FF miles and little interest in a typical mileage conversion.) So, to Marriott's credit, they are given an outlet - merchandise. This target audience could generally care less about the redemption rates - I see some options in that catalog that'll get you about a third of a cent per point. Good enough... (I tend to look for a penny a point when redeeming for hotels, measuring somewhat conservatively.)