After buying a few compromise windshells I finally broke down and paid full price for a Houdini; and I'm glad I did. Just took it for a test drive tonight, and had none of the condendation issues I did with the previous two. The others will be sold to help finance the Houdini.
My recommendation is search froogle and rank by price every couple days, and set up an automatic email alert for "Patagonia" plus "Houdini" at ebay. You might find an L on sale. Otherwise, bite the bullet and pay the piper. (Yvon Chouinard, in this case)
As an aside, the same cost/quality calculus applies to other items. I should have bought the smartwool bases, thermawrap insulation, and Houdini/ID eVENT shells in the beginning; had I known! I spent hundreds on a rack of junk. All you newbies, 'go to school' off us!