Just for the record, I'd stick with what Rudi says. I'd rather do more flights than having to argue my way through after the promo ends with each respective airline programme about OS/VO/NG flight numbers.

I'm doing LH-Miles and More, SQ-Krisflyer, AC-Aeroplan and maybe UA-Mileage Plus. I had already planned a RTW *A trip before this came about so the timing couldn't be more perfect.