With my first DC, I gave up bf at night because I couldn't cope with the lack of sleep. Later on, I wished I hadn't given up, for various reasons, mainly that she turned out to be intolerant to cow's milk and we had to get prescription formula etc.
DC2 I really wanted to get further with bf. Again about 10 days in I found the lack of sleep impossible to manage. Maybe she was a bad sleeper anyway, but I ended up co-sleeping, which I never intended to do. She pretty much fed on and off all night, but I just popped her onto the other breast if she woke up and went back to sleep. It worked well for me. I fed her for 18 months.
Pros: After about 2-3 months, bf was much easier and cheaper than FF - no need to prep and sterilise bottles and carry them around, I could just whip out a boob wherever we were.
DC2 does seem to have a better immune system - fewer viruses, especially tummy bugs.
I got more sleep bf and co-sleeping with DC2 in the difficult early weeks than I did with FF DC1.
Cons: DC1 is 6 and still.comes into my bed at night! I probably wouldn't have co-slept if it hadn't been for the breastfeeding.
FF DC1 slept through the night by 12 weeks. Might just have been a coincidence of course.
BF DC still took quite a long time to feed, even up until about 6 months. She was never a 10 minutes feeder, so I had to devote quite a lot of time to feeding.
Having tried both ways, I would choose to bf again if I had another. I ended up enjoying it.