I think Delta allows spouses, but not companions on your travel benefits.

You get your parents and spouse on your delta benefits. If you aren't married you can choose a travel companion.

If you are single, you can have one friend on your Delta benefits. If you are married, then no friend. United, you get two friends if you are single. One friend if you are married.

Actually in my opinion deltas travel benefits are the best we have.
That's not to say you will always get a seat. But I guess that's why it's "space available"

I've had really good luck non-revving on Delta. Even better when it is a Skywest operated flight and I have been given a business class upgrade several times. On our own metal, we get priority over mainline employees.

Everyone bashes our united benefits as well, but I've also had really good luck.

Honestly I feel our priority travel bennies suck relative to others but prefer our system of being able to list on typically three different major airlines. The problem is the 175.

Where you are traveling to/from or even international vs domestic should formulate which airline is your favorite nonrev carrier. Delta is most likely to have seats available and also most likely to have a comically long standby list.

United has the best standby lists. ORD-DEN. Oversold by 40, 4 jump seats, 53 on the list. 737-9

"Current position when using a Personal ePass 217"

Domestic non-rev on DL is tough, but international....oh baby!

Delta benefits are the best we have. How's all this different some United? It's not. Non-revving out of any airlines major hubs is going to be difficult. And I can't think of many non-hub flights that exist anyway. I've non-revved all over the world and been in business class almost every time on both United and Delta. Of course I look for flights that are wide open and go during the non-peak months. Going alone makes things easier as well.