The silicone on the lid doesn't keep the lid on. It just pops off when my tea is hot. This defeats the purpose of having a to go cup, and since the lid is glass, it's also dangerous as it can/will fall and break if I try to move around with it.
Since viva doesn't pay the shipping if you want to return something, it's not really worth sending back. I'm sad because I was super excited about having a glass tumbler. I wanted to use it with my colourful teas.
This is a fail for me.

This is my second purchase of this style. This is my favorite hot mug. I use it for tea and or coffee.

Best mug ever!

It’s perfect!

The only cup I use for my coffee/tea due to its design and functionality, I don’t have to worry about it toppling over.
The glass is strong and heavy duty, so they last years and look brand new. The mouth hole looks small but it’s pretty large.
The shape (width) is perfect, its pretty ergonomic, and fits nicely in my hand.
The lid seals perfectly I’ve never experienced leakage. The silicone is of quality and doesn’t turn white when stretched.
Water doesn’t seep under the silicone sleeve, so you don’t have to worry about trapped water behind the sleeve-it’s very hygienic.
The sleeve can also be removed easily.
The cup doesn’t stain, or absorb smells.
NO CONS !