I was in a tough spot with this, once. A neighbor/friend of mine purchased a brand new SRT10 Truck. Back in 2004, when these things were HOT,HOT,HOT. I mean, he had one of the first ones EVER. Ordered it and all. He pulls up with the Temp. tag on the the window, and about 25 miles on the odo., (literally on his way home from the dealer picking it up) and throws the keys to me. Says "take it for a ride". So, I did...... LOL. It was fun, and I appreciated the gesture, and the trust he had in my driving.
Fast forward, a few years later, and I got my 2006 SRT10 VOI9... He is out front like a kid in a candy store, eyes wide open, drooling watching it pull off the truck. So, yes.. I threw him the keys... For a few reasons.. He offered/insisted I take the SRT for a spin, and #2, he never asked... I offered. And third, this is an experienced driver. He's had 10 second Gn's, Viper truck, harleys,etc..
He took the car down the road for about 1-2 miles, turned around and came back. That was it. no speeding, tire spinning or anything. I had my eyes on him, though. LOL.
So, it really depends on the situation. But I would do it again, the exact same way...