Welcome to FT, bizflyr26!

You'll find most questions like this have been answered in excruciating detail somewhere in the UA or US forums.

A brief intro. thought - it's usually better to have lots of status on one airline as opposed to low/middle status on two.

It's usually best to pick the airline you'll be flying the most and use that carrier, and frequent flyer program, almost exclusively.

Altho it's relatively easy to fly US and credit the miles to UA, or vice versa, in practice it's been frustrating, at least for my attempts to fly US and have the miles credited to UA. Most carriers set it up so that if you want to take advantage of, e.g., Premier status w/ UA and have access to E+ seating area, you have to fly on UA and be using your MP number. If you fly UA and credit the miles to US, you probably won't have access to E+ seating except perhaps on date of travel,

If you are flying US and crediting miles to UA, you probably will not get complimentary upgrades on US, even if you are say Platinum in the US program. US wants to restrict free upgrades to those who have US status AND are crediting the miles to US.

I've been Platinum on US and switched to UA, am now 1K. UA has been better both in terms of product and routes that I fly. For you, US may be a better choice, but what counts is not so much what happens next month but your flying patterns for the next few years. Hope this helps.