I've transported many dogs (and a few cats) in the cargo hold - I occasionally volunteer as a "transporter" to help with a dog rescue.
Generally speaking, the dogs were fine. A couple were a bit "weirded out" but quickly recovered with some attention (snuggling, walks, play).
Your experience may depend on the airline in question - the one I use most (Alaska) does a fantastic job with pets in the hold. You may want to research the experience of others for your specific airline.
But - in general, for most dogs - it will be fine. And one hour is a nice short flight to try your pups out and see how they respond.
Oh, also - there was a period of time when people recommended drugging your animal, but that advice has changed. Imagine being stoned and thrown into somewhere loud and new and perhaps a bit scary; that wouldn't be a great experience. So no drugs for the pups. You can get some wine for yourself it if helps you relax :-)