This bottle is a good idea but it needs better execution.
If you tip the bottle back and suck and then put the bottle down, water will leak out of the spout EVERY TIME! You have to continue sucking the spout after you have topped the bottle upright again to remove the water between the filter and spout, otherwise it leaks out. 
This make an annoying and attention seeking noise which is awful. I get some right funny looks. 

Also the spout is quite firm and I can't pull it out easily without nails so I have to use my teeth.