Child seat: regular bike vs. Yuba/Xtracycle
 

My daughter is getting close to the age where she can safely ride in a child seat on a bike. I'm deciding between putting a rear child seat on a regular bike (something like a Yepp Maxi) or springing for a longtail cargo bike like a Yuba Mundo or an Xtracycle, also with a Yepp. It seems the longtails are much more stable for loading/unloading with just one adult, which would be really handy. What are people's experiences with using a child seat on a regular bike? Is it preferable to have two adults? Part of the use case would be picking up from daycare after work, so I can't always count on a second adult being available to help.

Most people here, where cycling with babies is very common, use a normal sturdy step through or top tube upright bike, with a double kick stand and a device to stop the front wheel from swinging while on the stand, with a front seat which is nicer for both the child and the parent. I guess stability is more about weight distribution, trail, swept handlebars and the leverage of the upright posture than about wheelbase. Due to the nature of cycling here any bike significantly longer than the majority is a bit impractical, but I've never understood why anyone with less than four children or other specific cargo would want to ride an extra long bike.

Nothing wrong with help, but I believe you should be able to load and unload by yourself, which isn't that hard.

It's okay with 1 adult, nothing too difficult.

And...
 

[FWIW] Topeak Child seat rack combination is made to allow easily removing
the kiddy seat when not required..

https://www.topeak.com/global/en/products/child-carrier

I've seen several people who were very happy carrying kids on a cargo bike.

How old is your daughter?

I wonder if there would be an age difference. I think of kids in child seats as being young. 2 years old? While those on cargo bikes a bit older... 3 to 5?

At some point you'll have to decide what is next. Something like a WeeHo, or some kind of pedal trailer? Even if the kid doesn't provide a lot of power, every little bit counts. :)

Or, get the kid onto her own bike as soon as possible.

Anyway, thinking about what is coming next may help you choose what you wish to do now.

My wife used a regular bike child seat when our youngest son was <2 and the older two (3/4) were in a bike trailer. All she had was a typical women's hybrid bike and a single kickstand. I think some of this is going to be about weight with my wife weighing enough (don't tell I said that) to overcome the added weight of the child seat riding high on the bike. Up until our daughter was 6ish, I had her on a Yepp Maxi on my longtail and as long as she was ahead of the rear axle, I had no issues even if she was leaning over or moving around. Again I have the weight (I'm just inside the range to be considered a Clydesdale) to overcome her weight moving around. For someone more on the petite side, a lower center of gravity setup would be more ideal. Bikes like the more modern longtails using 20" tires or bakfiets style bikes.

I just used a basic road bike and had the Topeak Seat as mentioned above. My kids where able to comfortably ride in the seat at about 10 months. The seat is fairly simple to put on and take off if you'd rather ride without it. My kids seemed pretty comfortable and often fell asleep. I felt that it adjusted well to a growing child and secured them rather well. I didn't have issue with being the only adult loading and unloading.

Our first child were used a trailer until she was old enough to ride on her own, then next child wife wanted to try ibert, it's kinda a pain on some bikes (the child goes where you stand during dismount) but the kid loves it, so I guess it's worth it

Do you foresee the long tail cargo bike useful after the child has out grown the kiddie seat ?

afterwards you could rig up a 2nd seat, handlebars and foot platform/pegs on a long tail ,
to let them continue to ride back there for many years..

I was not a fan of child seats on bikes. I preferred a trailer. My thought was if the child is in a seat and something happened that I crashed, then the child would crash also. In a trailer, the bike will rotate around the hitch making it a lot less likely that the trailer would roll over. Also, you'll get many many years out of a trailer. A seat is really only good until the child is 4 or 5. I used our trailer till the child was 7. And the trailer can be a gear hauler once the child moves to a trail a bike or is riding on their own.

Look at my profile pick. The trailer works well if the child falls asleep. We made many trips to a park carrying child and picnic stuff in the trailer. Junior gets playground. Daddy gets his bike time. Junior naps on the way home.

My 2 cents