I currently have about the same amount of status miles on both my AA and UA accounts. If I make a trip to the USA later this year, I will most likely accumulate the needed 25k miles for the lowest status of one of these programs. My question is: which one will give me more benefits? Here is some background information.

This year I have had Silver Medallion status with Delta. So far I have absolutely loved it! On two of my three Delta flights this year I have been ungraded to First (domestic) and on my KUL-CGK-KUL KLM flights I was automatically put into Economy Extra. I purchased all the mentioned flights in the lowest fare classes. Of course the free baggage is also nice, but you get that from al the largest US carriers.

Which of the two programs would give me similar or better benefits for next year? I travel basically all over the world, so I really would appreciate benefits on for example Lufthansa, BA or even Finnair (in the DL/KL way) and not only on the US carriers.

Also, will the status benefits (most importantly free bags on US domestic flights) start as soon as I have accumulated the 25k miles or at some later point?

Thank you!