We've been exclusively breastfeeding for 6/7 weeks, I decided to pump and mix with formula. That's been going well, sometimes we give just an ounce or 2 of formula (if he's still hungry after 6oz) and my son makes a disgusted face and rejects the bottle. Usually I mix 2oz breast milk and 4oz formula, he's happy and sucks it right down. Do you think trying a different formula would help? Or do they all "taste" the same? We use Enfamil Newborn.