Kind of hard to address the original question without more info from OP. Which routes? How many miles do you expect to fly (enough to get 100k status)? Is money an object (presumably the case, otherwise you could just buy J?

In some cases it may make sense to go with an airline that offers frequent discounts on paid J, i.e. Continental to Europe, though that might not work depending on the routes. In other cases AA discount fares + Co-pay + miles might be cheaper. Or perhaps UA if you don't mind paying a higher base fare (though you will have trouble finding any upgrades to Australia in C using miles)

Yet another factor is the quality of the product. I would far prefer a lie-flat seat in NZ business class than the crappo UA and AA seats (though those will improve as they are replaced).

Yes, it looks like the OP kind of bailed from the discussion?

I'm back (OP). I fly to Milan six to eight times a year as well as plenty of domestic travel via air. The NW MSP to AMS has been the route I've taken lately. I'm in Omaha so am always connecting to a hub, MSP,ORD,DTW are the usual connections. This gives me UA and NWA. I can fly directly in to Milan from ATL but the flight tends to get a little long when in coach.
I had my sights set on NW but have just found out they don't have complimentary upgrades for Platinum elites. Aparently I still have to cash in miles and usually purchase a higher fare.
BTW I have 140K one pass miles but CO is not working for me any more for travel in the states.

Not being particularly familiar with BA Executive Club or CX Asia Miles, I can't comment too much. However, the BA forum seems to claim that a roundtrip UK-US MFU from WT+ (even discount fare basis T) is 25,000 BA miles. Of course, earning 25,000 BA miles is pretty tough unless you tend to fly either premium (WT+ or better) or short-notice (Y,B,H) fares.

The deal isn't so good with CX Asia Miles for BA upgrades, from what I can see.

Getting to Milan on AA means you connect in Europe somewhere as well, as they aren't operating to MXP (service starts May 2008). This means you don't get upgrades on the intra-Europe legs, of course. UA doesn't fly to MXP either, instead depending on Lufthansa. You can obtain paper SWUs for LH flights in UA MP, but their usage is restrictive too. Check the UA board for more details.

Remember that "complimentary" means that you flew a lot. UA and AA don't offer systemwide upgrade certificates until you reach their highest tier.

It's pretty easy with the BA Visa...

Do you get the 6 SWU for reaching 1k with United each year or is this a one time thing?
And a SWU means upgrade to the next class for one segment no watter how many miles it is?

Cheers

Unless you buy higher fares at BA, don't even try to earn your BA miles by flying. 50% bonus for transfer from Diners Club typically at least once a year, 500 flat miles for even a one-day cheapo rental with Avis (but must use BA's AWD) when other airlines would only get you 50 miles, 500 flat miles for cheapo one-night Candlewood Suites stays (which with other airlines would earn you only 1 mile per $ spent), etc. Plus, of couse, all the usual partner activity (where in other cases you'll at least earn about the same BA as with other airlines).

And, depending on where in the US you are, it's a lot easier after you do one such upgrade. That's because to upgrade to C you have to buy a WT+ fare, and on the WT+ fare you earn well, and from the western US you earn about half as much back as you spent on the upgrade! Thus you don't draw down your net BA mileage nearly as fast as it would seem by using BA miles for such WT+ to Club upgrades.

You get 6 SWUs each year you reach 1K. They're good for 13 months. For example, if you accumulated 100,000 elite qualifying miles (EQMs) in 2007 you'd have 6 SWUs that you can use from Jan. 1, 2008 through Jan. 31, 2009.

Note also that, as most but not everyone on FT knows, EQMs are not the same as actually flying 100,000 miles. For instance, if you fly business class you get bonus EQMs.

As for your second question, the SWUs apply to more than one segment. So if you were to fly Denver-San Francisco-Tokyo-Hong Kong on United (if that routing still exists), you'd be upgraded all the way. It would take two SWUs to upgrade round-trip. The caveats for this are that the upgrade space must be available to use the SWUs--the further ahead you buy, the better--and that you can only get the upgrades once you buy the ticket, not simply reserve it. But you can check beforehand just before purchasing to make sure it's available--I do it by phone with the reservations agent, but I think you can do it online through the UA website as well.

You can even upgrade, say, NRT-SFO-FRA with one SWU under certain conditions.

This is good info - I am DL Plat, but it doesn't do crap for Intl upgrades

You also accrue an additional 2 SWU's for every 50K EQM past 150K. Unlike the initial 6 SWU's, these are available as soon as you earn them, not the year after like the original 6. Also, many people purchase full fare B/Y tix and then use 30K RDM's to upgrade the whole roundtrip.

A good strategy is to purchase full fare B/Y, upgrade using 30K miles. You then get an 50% EQM fare bonus. If you flew 67K miles this way, you would have already reached 1K status.

In many markets, you'd make UGS while at it. Your strategy uses a lot of money, especially if you're flying international B/Y.

OK...show me an approach that gets you consistent international upgrades to C on the cheap. I'm all for it.

Buying UA Z-fares when they show up? Z is sometimes cheaper than B, and saves you the miles to boot too. Of course, 50-day advance purchase and tight availability count against me, but upgrades to J are capacity controlled too. And there's no risk of losing an upgrade due to equipment change; Z is paid business class.

Sample: SEA-FRA on UA
ZSPECE: $3202.00
BEE: $3675.00

Honestly, if you want consistent (near 100%) upgrades, you buy the class you want, or have some checking of inventory before you begin booking. The SWU/miles from discount economy route is not bad. Expensive on the miles, but miles are comparatively cheap to dollars.