Meg is a great sleeper, and has been as long as I have had her. I can wake up in the morning, turn on the TV, lay in bed for an hour, check my phone - she's still asleep at the bottom of the bed. As soon as I get up and ask if she wants breakfast, she's ready to go, but she used to lay there until as late as 10 am if I did (that was BG - before Gusto).
Gusto has learned to be a better sleeper. He used to react, not to my alarm going off, but to the nearly silent click the alarm makes before it goes off. He'd be on my face instantly. If I got up to pee in the night, he was up and wondering where I was going and could he please come too? He now sleeps better, although never late. I can get up during the night, and as long as I close the door behind me, he'll stay in bed. He wakes me up early if my alarm clock doesn't go off (I was stunned to sleep to 7:15 a few weekends ago; it is possibly the first time I've slept past 7 am since I've had him), but he will just cuddle for a bit and then curl up and sleep again if I turn on the TV. If I wake up before him, he'll stay sleeping as long as I stay in bed.