Nice analysis. As always, I must point out that Hilton prpoerties treat me like a King on priceline stays by providing Gold benefits (even though not required to do so) while SPG does not and usually provides the worst rooms (even though not required to do so). With more leisure than business travel, I am extremely price sensitive, and Hilton properties are often cheaper and generally provide the most bang for the buck.

That being said, one cannot discount the value of SPG's frequent promos. Last fall's buy3get1free offer was almost as good as Hyatt's FFNs, and the points+$ offers are generally more useful than the rarely useful pointstretchers.

But as to the original topic, I find that I tend to accumulate Marriott and HH points more rapidly than SPG points (even after adjusting for the 10:3 ratio) so I find better value with Hilton and Marriott, absent free room promos.