I have both bt my baby drinks better with avent.
This is my first baby and I've got avent bottles. Not really heard a bad thing about them either.
I used Avent with my first 2, I plan on using them again. ..
I use the Avent bottles and think their great. Rather then tryimg to find different bottles to suit baby I just upgraded the nipples to the flow he liked as he grew up. He's now 14mths and just has 1 bottle at night but we'll do the same for this one when its arrives.
Tommee tippee are ok. I tried with my son and he didnt.like it. I prefere drop ins
Supposedly, Tommee Teppee is the best; they are expensive though!