Yeti Rambler 20 oz tumblers work very well, keep ice solid for a long time, and warm drinks warm. But, personally, I use my tumbler in the car, and, if falls over, water (or other liquid) pours out of the drinking opening onto everything it touches. This, to me is a design flaw, there was (is) no way to prevent the spilling when you carry this in a back pack, or on the front seat of your car.
Enter a solution, Amazon sells many after-market caps, with various options, such as a smaller hole for a straw, or whatever. But most are very over-priced in my opinion. Then, I discovered this one (see link above). Only $2.19 with only 99 cents shipping charge. It was shipped from Poshan City, China, and it arrived today. I love it, very impressive clear plastic and the seal over the drinking spout is very well designed, and should seal off any and all leaking. It also fits the Yeti perfectly.
So, if you want an alternative for your Yeti Rambler, here is the perfectly reasonable place to get a high quality, “Yeti” quality, compatible, solution to spilling. Added convenience with very little extra cost.