Great with the black cap not the steel one
Great product and nice idea to have a stainless steel cap too, We all need to be drinking and storing in steel, not plastic.
Even the good BPA free stuff (Nalgene etc) has now been proven to gradually breakdown.
The only thing wrong with this particular one is that the steel cap grates when you screw it (as you might expect steel on steel too).
I returned this and went for the same but in a colour - they come with the black cap, which is plastic.
It means there is plastic when we're trying not to use plastic, but at least it is only the cap.
The quality of this product is superb, bottle for life.