Originally Posted by
ghostboy
So why not stick with NW unless your routing is changing significantly, or you're moving away from a NW hub?
I don't live by a hub. But the reason is that NW is top heavy IMO and direly need to thin the herd. Markets like SFO are just awful for upgrades as that city has too may Platinums. I figure a four tier program might be better for me due to my heavy mileage.