I went with a trailer and most of the time stayed on side streets. If I were to tip over the trailer would remain upright and same if the trailer tipped over, I'd remain upright, baby suspended in his harness (yes it happened, no harm but for one very angry little boy....don't forget the helmet).
Everything went in there, toys, juice, pillow, blanket, food, etc. Mine was such that a cable could easily be run through it for locking up. There was also room for small side-trips to the store.
Can't say that about a baby seat, which I did get my foot caught in waaaayyyy back when I was a passenger in one. Then again, tons of people use them without a problem. I know I was dropped helmetless from one several times without too much damage.....
Something I've noticed in my area whilst riding around with a two-kid trailer:
1) Surprisingly many didn't realize there was a kid in there.
2) Motorists are more careful when there's a flag on it.
3) But not all motorists all the time, so be really careful.
I used to have an open mind but my brains kept falling out.