My dad was 25 when I was born, so that was always the benchmark for me growing up. I blew right past 25, 26,27,28, 29 and when I hit 30 I told myself that if I wasn't at least with the woman I was going to marry by the time I hit 35 I was going to be a bachelor for the rest of my life. I promptly met my wife, married her and by the time I hit 35 I had 2 kids and the third (last) one on the way. I felt like at 32/33 I was getting a late start, but as it turned out, I reconnected with several people from my old neighborhood/HS and they too had started around the same time, so there was a small group of us who were the same age and whose kids were the same age. There were also a couple of dads a good 8-10 years older than me with kids my kids' age, and I marveled them for their parenting skills. It had also helped that for both of them, these kids were from 2nd marriages and they also had adult age kids, so I think for them, having a second round of kids energized them or at least made them feel that since they had been through it once, the second time around would be easier and they would have some insight they didn't have the first time.
Conversely, the parents of one of the kids I grew up with didn't have kids until they were near the end of child bearing years (IIRC, the mom was in her 40's when he was born, and either late 30's or 40's as well when his older brother was born), and the dad was at least in his 50's when my friend was born, and while the mom was sweet as can be to all us kids in the neighborhood (and why not, she was as old as our grandmothers), the dad was old school and didn't care/know anything about 'modern' parenting. The older brother was unabashedly his favorite (one Christmas, he got a $2000 electric piano/organ, and my friend got electronic Battleship and repairs to his bicycle), and was otherwise such a curmudgeon that he embarrassed my friend to the point the other kids in the neighborhood (I admit me as well, but to a lesser extent. Not that it really matters and may have been even worse) teased him mercilessly as well. Saddest part is this kid was arguably the smartest kid I grew up with but so socially awkward that he ended up being his own worst enemy.
Having said all of that, I think the "pros" and "cons" are meaningless as long as you understand and stick to your role and responsibilities as a parent. My experience has been that it's a crapshoot in the end and you have to figure out what each kid needs from you, and sometimes even that isn't enough; just love them the best you can anyway and keep figuring out how to do that better.