Definitely 1-2 for me. 0-1 was ony hard the first month or so, since I had no clue whatsoever about babies. But once we got beyond those first few weeks of cluelessness, and learned that newborns want held mot of the time and don't actually like being laid down so you can do your own thing like most childless people assume, lol, things got much easier. He was a super happy, easy going baby, so it really wasn't to hard with him once we figured out how to care for a baby.
Going from 1-2...well, DS2 wasn't near as easy going as DS1, so he kind of completely shocked us. We weren't used to dealing with so much fussines over every little thing, so it was difficult learning to adjust all over again. I thought I was prepared from DS1, but he really didn't prepare me for a fussy baby. he's still a very fussy toddler, but now I'm more used to it and adjusted to how to handle him, so its not bad anymore. Definitely a shock to the system at first, though!