Well, stopped at a Buc ee's this weekend while heading back to Arkansas, and picked up 4 of the 30oz RTIC cups. My daughters have been hounding me for there own Yeti and owed a buddy for feeding the dogs.
I did a simple test and they seem to be just as good as my Yeti 30oz.
Filled both with ice water to cool them both before the start, emptied them and filled with ice where I could still put on the lid, and filled with tap water until full at about 3:00pm.
The next morning they had about the same amount of ice & water. Took mine to work and left the RTIC. When we got home after work and school the RTIC still had enough ice to "clang" when moved.
They are 50% of the cost and work as good or at least 90% as good as my YETI. Now to see how they hold up with use.
May have to ponder a cooler now.
Edit: Lids seem to be interchangeable, but did not try a spill test