Excellent for mixed feeding.
These tests are great. I've found that I can go back and forth from breast to bottle (expressed milk but in theory would work for formula top ups too) without a fuss. I had to express and bottle feed for an entire week when my baby was just going on a week old, I had concerns about whether or not she would be able to latch back onto me (we're always told.all the stories) but there was no problem at all.i switch it up often now and there's never been issue getting her back onto the breast. Also, the teats are durable. Nice, thick silicone that doesn't split after few washes in hot water.