You might as well forget CO about a biz class seat to europe with miles.

The capacity controls are relentless on CO. There are very few seats available for outright purchase with miles. Fewer still are the seats available for upgrade.

BTW you can only upgrade to Biz on CO by buying a H K or Y fare (HoKeY). You can upgrade on lower fares by paying a fee (I belive its like $400 each way).

Stick with AA, don't waste your time with CO. For more info goto the CO forum and search on "BF upgrade" for a good laugh.