Yea, the GE helps.
It did mean that I had to take some time to coordinate my schedule with available CBP interview slots.
And no, such slots were not available near to my home in PHX. I think LAX is (was) the closest, but a DFW appointment ended up slotting against a time frame I was there.

I know TSA is expanding the Pre-Check concept (including on-the-spot random pulling "general" folks over to Pre-Check in the security lines), but taking the time to submit to a background check and a personal interview with CBP goes a long ways in getting TSA to recognize you as a "trusted traveler". Much more than hoping UA will "sponsor" you.

As for any UA sponsorship, in my case (being 1K), they did reimburse me for the GE fee.
But it still required my personal time for coordinating the CBP interview. IMHO, it was time well spent just for the GE benefits. The high TSA Pre-Check selection ratio was just an added benefit.

I agree with what others have said ... airline "sponsorship" for Pre-check will become a thing of the past.
At first (IMHO: the beta test mode) it made sense to extend Pre-Check to GE/Nexus as they had already been declared as trusted travelers. Once that level of folks passing thru was handled ok, it made sense to extend the program. Extending to airline Frequent Flyers seemed a logical next step. As more checkpoints received Pre-Check (and as the knowledge of the concept grew) it made sense to extend the benefits randomly to "general" flyers. Doing this "advertises" the concept to more of the flying public. At that point the TSA can now offer the service as a "paid subscription" for folks willing to submit to a background pre-qualifying check. With more and more of the general flying public being qualified, the concept of offering the service to frequent flyers (as a promo to advertise the new benefit) is going to dwindle.
If you want it, then commit to the personal time required to actually qualify versus trying to piggy-back on various temp/promo "qualification" methods.