Nicolac,
Sorry , didn't mean to offend, I certainly didn't think, or mean to imply you would leave the baby in their for hours. But like Mama sunshine siad in her post, initally baby might not mind, but then they won't like being in there, and won't use it much. Baby will still be young enough that you will have to baby proof your house anyways.
For me, I 100% childproofed my main living area so that I could do dishes, or cook, or blow dry my hair, shower, etc and if baby was awake and on the floor I didn't have to worry. This worked really well when my second son came along as when you are busy with the baby, my 2 year old would have to be by himself sometimes and I didn't have to worry.