This tumbler set is great. I'm not sure that it is stainless steel though. I've been told that a magnet won't stick to stainless steel and it does stick to these tumblers so that is still up in the air.
That said, they do work well at keeping hot drinks warm and cold drinks cool. For this reason alone I do like these tumblers. They are not glass or plastic so they will not break easy which is another plus. All in all I do like these tumblers because with children in the house, we all know that glass and plastic break. I think it's safe to say that I will be using these for quite a while.
You can get this set for yourself on Amazon here.
All in all I really do like these tumblers. I just wish I knew if they were really stainless steel or not. It would help to know if acidic drinks are going to stain the metal or not.
Have a great day!