A downside (at least for me): Waking me up at 3,4,5 in the morning crying for wet food even though I just gave them wet food hours before. Spoiled brats!
As much as I love cats, and my own cats in particular, I refuse to budge on the issue of who is the pet and who is the master. The first time a cat wakes me up, they go flying across the room. They might take a bump or bruise, but they'll recover. By the second time that happens, they know better than to wake me up. They'll bug my wife or my kids, but they don't mess with me.
Same thing in the kitchen. We set out food at 6 AM and 6 PM (as opposed to just leaving food in the dish all day, which I know works in some households but not ours) and when it gets around 5 or so, any time anyone goes into the kitchen, they're whining and meowing. They have learned not to bother me. I won't kick them, but I'll use my foot to launch them across the room. Again, they're smart animals and they learn quickly. Bothering me will not result in food; it will result in unpleasantry. I will feed them when I decide to.