I was given a very similar one by a Dutch Army colleague - they were recruitment gizzits. Frankly, I'm not that impressed. You can't heat the cup and it doesn't hold much fluid.
Personally, I see it as a 'single use' device - I want at least a couple of functions from a cup. I would prefer to carry a bigger metal cup you could cook with (Crusader-stylee).
Having said that, they are small and convenient and I might pack one in a vehicle kit - cook on metal, decant to plastic cup, maybe? Good for picnics!