My answer would be yes - either set of grandparents.
I'm also surprised at the amount of No's.
I would feel like I was missing out on my relationship with DH. We go away alone somewhere for a week every year near the date of our anniversary.
DH & I are going to Jamaica on Sunday & on the way are dropping our 3.5 year old and 8-month-old DS's with my parents for 8 days.
Am I worried? Not at all.
They have legal documents listing medical information for each child and authorizing them to make decisions on our behalf, cc of birth certificates and immunization records, ans a complete schedule of when the boys eat/nap/sleep along with a list of DS1's fave foods.
My parents are sound of mind and body, and have planned some fun activities for DS1.
I certainly understand not wanting to leave children if grandparents are fragile or abusive.
But otherwise, why not???
It exposes them to different households and methods which I think inspires healthy flexibility in children. And, allows parents to find themselves and each other again - which seems very important. I know when I'm recharged every once in a while, I become a better parent.