I ruined my Oxo Good Grips coffee travel stainless steel mug through putting it in the dishwasher.  It was my favorite, because of the push button (push button, open, press again, closed) system that prevented leaks. I noticed how expensive it would be to replace the Oxo, like $30.  I then ordered several popular stainless steel mugs.  My criteria--had to be 16 oz., stainless double walled for keeping the coffee hot for hours, and a leakproof design, no handle, and be inexpensive.  I have been through dozens of mugs that did not hold up, or the lids get lost, so I had a cupboard shelf full of inoperative travel mugs.  I have tried the ones with the flip open tops, where half the lid opens, unfortunately the lid is right up to your nose as you sip.  One I tried was this one from Bubba Brands.  The shape has a good feel in your hand,it holds 16 oz. but is not "bulky".  The lid is a simple design--a flip, snap cover over the drinking hole that then snaps down, out of your way as you drink.  Being new, the flip cover snapping into place is a bit hard to do with one hand.  I think that will loosen a bit with use, hopefully it will be a long time before it is loose enough to leak a little.  But the seal seems very tight, and the coffee stayed hot for hours, (even with the hole uncovered).  For the money, and I paid $13 (it is closer to 16 in other colors), and the beautiful lilac color, I am satisfied.  This thermal mug feels substantial, not bulky, and all of it is very simply designed and easy to clean.