One of my two dogs is 90 pounds... he fits okay except the front seat is more backrest than cushion so he spills out of the seat a little, LOL.
Like kids, the rear seat is safest but our cars at least have the sensor to know not to set off the airbag when there's not enough weight on the seat.
My dog won't stay put in the rear seat though so it's pretty futile to attempt to put him back there. I should have him buckled in with a harness restraint but fortunately he lays down after we get up to speed right away anyway.
PS Oh, and premium as in leather? Lots of thick blankets to protect the seat and console then. Not a bad idea to cover the front carpet with towels either... my current dog doesn't get carsick but once you've had a dog christen a new car you tend not to want to take chances on that. :gringreen