Originally Posted by
ty97
The one facet that comes to mind (some will consider this a pro, some will consider it a con) is that the US system offers unlimited upgrades (space available, of course) for all elite levels. There are no 500-mile upgrades required.
Having experienced both approaches at multiple airlines, I much prefer the 500-mile upgrade version as a lower-level elite and think that AA's hybrid version (unlimited upgrades for EXP, but must pay for companions) works quite well. "Unlimited upgrades" for all just means that you don't get to choose the upgrades you really care about, but instead are competing with a lot of other "casual elites" who wouldn't even be in the upgrade pool for those flights if it were not automatic and free.