Teddy wasn't sure the first day (I got it pretty much right after bringing him home so he's had it pretty much from the start) The first day he wined a little and jumped out which resulted in him hanging over the side by his harness!
My daughter grabed him up quickly though and it was the last time he tried that.
He took to it quite quickly though and within the first couple of days began to really love it. He usually snuggles down inside and goes to sleep or chews his bone and is quite happy in it.
The first pic is Teddy I think the second day in his seat and the other is more recent.