I agree, the back is quite tall. My almost 4 year old can sit in it comfortably with plenty of room to grow. And the foot rest is nice, both of my girls can comfortably use it. And the handlebars are really nice. I am 5' tall and my husband is 6'2" and we can both comfortably push it, and he doesn't kick the back of the stroller like with the cheap umbrellas.
My 17 month old fell asleep in it the other day, and her head just tipped over to the side and leaned against the side of the stroller seat. It didn't flop forward or anything. It actually looks about like when a forward facing kid in a car seat falls asleep, their head just rests against the side of the seat.
I really wanted an orange or the lime green color Zapp, but I was able to find a used one for $150 locally so I jumped on it. These things keep their "resell value"!
It handles just as well with my 31 pound daughter as it does with my 19 pound daughter. And the wheels pop off of it to make it even smaller when folded. Like, you push a button and the wheel pops off and the when you want to put it back on, it just pushes on. Simple. The fold/unfold, once you get used to it, is a cinch. It's just 1, 2, 3 steps and you're done.
Have I mentioned that I love the Zapp?
Here are some quick pics I just took, if anyone's interested. Also, please note, in the pic with my older daughter the top looks "squished". Well, it is. I forgot to snap the top bar all the way out. Oops.