Thanks you folks are great. To answer the first responders - I have no illusions of flying in F on international. I'd be quite happy with C cabin. Any way I can do the math I figure it costs too much $$ and miles to get into F and not enough benefit. So I'm only after the Y cabin upgrade to C cabin. If I ever end up in F it will be for an op up and for no other reason because I can use the $$ and miles elsewhere. A full Y fare is likely close to the Z (heavily discounted) biz fare so no sense in buying true Y. What I really mean is upgradable Y-cabin fare like W as you suggest.
I'm on the fence about using these SWUs. Not many people I know use the loopholes to buy the biz tickets so I always feel out of place doing that - but frankly it's what allows me to do my job at the level that I do it. So I might just go forward with the Z tickets and call it a day - using the SWUs for shorter legs in region 1. I will stress about getting upgraded until it clears and I don't see the sense in doing that. I have to say I find both UA and CO somewhat annoying with the upgrades. I remember for years CO would not clear people until e.g. 30 days prior to travel. I got annoyed with that and stopped using them for upgrades. I finally used my CO miles to fly Mr BT2 RT to NRT on a saver award in biz. It's been a while since he's flown long haul international and was impressed with the old 777 seats - he's never seen the new configuration but will get to fly the 747 next month to SYD.

It would be great if we could combine a couple of SWUs and prebook a biz seat on the spot like using full miles for a C ticket. I like to think about my plane travel once and get it booked and then not worry about it after that.

Another reason I thought of for buying Z - I get the fare bonus on the EQMs which gets me closer to 1K next year. I got it this year with about 30K fare bonus EQMs.

My region 1 trips for 2011 include:

a trip to YVR - I'm on the fence flying AC on the E190 because I like those little tvs in coach they show good movies and they have 33" pitch. On UA I could get upgraded but its the UAX plane without a tv. On AC I gotta remember to book at last tango plus because of the EQM restrictions.

probably a couple of LAX-IAD runs - there I could definitely use the SWU or CR1.

a trip to PVD where I could also fly into BOS. I probably have a good chance for a UDU on those runs being 1K and all. actually I'm banking on having two trips to PVD this coming year. It's a toss up connecting to PVD or nonstop to BOS and then driving down 93. Come to think of it I may be in PVD three times in 2011.

a trip to ORD/Wisconsin area where I could certainly try for UDU although the ORD-LAX run often has 1Ks not clearing UDUs. But it's also only 4 hrs and not so bad in E+. I especially like seat 6C on the 319.

at least one trip to PIT. That run seems to have alot of UDUs clear.

I also need a trip to saskatoon but I'm likely stuck on a CRJ anyway for part of it without F class.