I changed bottles when he needed more than the 5oz and I bought the bigger bottle but I didn't change brand, I use MAM bottles
When my LB was born, we had issues with bottles tried, tommee tippee & Dr Brown. Didn't take well, we then bought MaM bottles and they suit really well, since 5 weeks he's had the small ones then moved on to the bigger ones, really decent too. X
The only bottle change I made were bigger ones when his milk intake increased :) I used tommee tippee and I’ve had no issues x