My only interest is in whether I need to consider my DH feelings when it comes to feeding OUR baby. He has one preference, I have another. Why do I get to make the decision?
Ignoring the issue of how formula compares to breastmilk completely - a major consideration for me, was, who does the work of feeding the baby?
DH only had 2 weeks paternity leave after each baby was born. He's a very heavy sleeper, which means all night feeds are down to me however baby's fed, plus he has the sort of job where he could genuinely be putting other people's lives at risk if he gets chronically sleep deprived. That leaves us with 2 days out of every 7 where DH can realistically take a share of the baby feeding.
So, given that even if baby's formula fed, I'd have to be doing the bulk (at least 5/7ths) of the feeding, plus any cleaning / sterilising during that time, I felt that it was absolutely fair enough that I should have the final decision about how our babies were fed. DH was happy to support whatever decision I made.
If breastfeeding goes well, then IMO the benefits of switching to formula so DH can help feed 2 days a week are far outweighed by the increased work created by formula feeding on the other 5 days a week.
(Especially at night. DS1 was bottle fed, DS2 breastfed, and night feeds were so much quicker and easier with breastfed DS2.)
Oh, and re. giving baby a bottle of expressed milk. DS1 - bottle fed on (mostly) expressed breastmilk till after we started weaning. No problems expressing lots of milk there. DS2 - breastfed. Expressing even enough milk for 1 bottle for him was a major time consuming PITA because my breasts couldn't seem to produce enough milk to both feed him directly and express enough milk for him to have a bottle from someone else later. I'm sure it works better for some people, but me getting any decent quantity of expressed milk for DS2 really wasn't easily manageable.