Agree with OP that purchase is worth it....and I only "bought up" to GOLD...
story is slightly different; though-
Gold in '07; I missed in '08. Got a message from US asking if I wanted to "buy up" to GOLD - and the price included a Club membership. Price was $350 or so. Between use of the Clubs (admittedly not the best clubs, but still...), the bypass of general security lines in CLT, and the fact that Mr. Sophie is 6'5" & those 1st class upgrades become critical for personal travel....it ended up being a great deal.
Missed again in '08 due to 4Q travel cutbacks....called US and tried for same deal. Surprisingly, agent extended status for Free. (but no club membership) Admittedly, was only about 8 segs short, but FREE is Free - especially from US.
SO - If one has until FEB to make the decision w/out many flights beforehand, may be worth it to wait (or call) to see what US will do on their own....
My experience has been that time of day plays the biggest role in securing upgrades. With flexibility in that aspect, I was 42/48 in '09...and the 6 missed were either last minute changes OR 5PM Thurs flight.
Also have found the priority boarding at the higher level to be worthwhile - CLT has A LOT of Silvers!
Now, based on this thread - and the fact that flights are reduced - am wondering if I should buy up to Chairman or at least PLAT???