I have the outward hound seat, I just bought a week ago. Here is my story:
I took him to the vet and ran other errands and he whined the whole entire time!! He was in his airline carrier which I let him sit up so he could see but it didnt help. I knew I was going to eventually have to invest in a car seat but tried to put it off. He was so outdone with that bag, he climbed out and layed on the seat of the car (see pic)
Because he drove me crazy with the whining, that same day, I went to Petsmart and bought the seat and put him in it. He seemed to like it. He didnt cry as much, he actually fell asleep but I think by then he was so tired he couldnt help it!! Plus it was better than the bag. Seriously, its like having a kid!!