I never co-slept with Sweet One but I have been with Little Man. It started because I was by myself at nights in the hospital and it was easier than ringing the nurses every time I needed to get him out of the crib. Also, the first night he insisted on nursing for almost 3 hours straight so it was impossible to get any rest without just falling asleep while he ate. (And yes, technically the nurses are not allowed to let him sleep in teh bed with me but they turned a blind eye and for this I am deeply grateful!)
When Sweet One started out, feeding her was a great challenge - which we overcame despite many swear words and tears. Luckily, since I already knew what to do, it was much easier to get things going well with Little Man. While Sweet One would have been taking 30-45 minutes for a feed at this time, Little Man only takes 10-20! And yes, it is enough as I only have to feed him every 4 hours at night. After I'm done feeding him, it usually only takes a few minutes to get him sleeping while Sweet One would often cry for up to 20 minutes. All of this leaves me getting more rest and not stressing myself to tears every time he is hungry!