Our WKORV and WKORVN units both give 148,100 SO = 80,000 SPG.
The 4 years 2006-2009, I converted WKORV (annual) and WKORVN (even years) for a total of 480,000 SPG points. Someone can add up the MFs, but let's say for the sake of discussion that they're somewhere around $12,000 for that period.
I used those SPG points to get over 100 days of holidays staying in Starwood-branded hotels for a month in Europe, multiple 2 week trips along both coasts of the USA, a couple of winter weeks in Whistler and Aspen, 2 weeks in the Bahamas, etc, and dozens of short weekend getaways.
If I'd paid for those same rooms using Starwood's web site at the same time I booked the room with the SPG points, I would have paid approx. $45,000 -- the 29 days in Europe in mostly suites gave me over $23,000 of value alone. I'm a little OCD that way -- I like to keep track of how much I "saved".
I am not suggesting that this is by any means a typical expected return on the MFs, but for me, this specific type of use was part of my calculations when I decided to buy in to SVN instead of one of the other timeshare systems that we'd been introduced to over the few years previous...