Oops. I forgot to say that anything that nails down requirements 1-4 works great, whether you buy it at TTR, in a store in Cancun, or you grab your favorite one from your house.
The bubba mugs are a great place for packing the bikini bottoms in your luggage All in one area and once you get there and check in, you have your swimwear and your drink cup all in one spot. Bammmmm you are ready to party! Bubba is just a brand name. I do suggest getting an insulated cup with a handle and a place to drink from that does not require a straw all the time. Drinking beer through a straw all day tends to lead to some memory loss times at TTR.
Thanks for all the responses! We have brought our own insulated mugs or sports bottles in the past but I was curious about the "Bubba Mug". I had never heard of that brand until this board. It's been a few years since we were there... The 22nd can't get here fast enough!!
If you do not bring your own mug of some sort, you are left to drink child size glasses for your trip. Which I did, ahha. My advice if you do not have your own cup is to always order 2 drinks for yourself each time you go to the bar. Other great advice I read on here. When your bottle of water in the room runs empty (about 8am in my room), you can bring it to the bars to refill. I did not think of this nor do this on my last trip, I certainly will on my next trip.