As someone who loathes flying with the heat of a thousand suns and who has taken that route on Amtrak, I'll be happy to try this service at my next convenience.
I don't hate the ride on Amtrak, but it's a hard route to sleep, since it's just a little too short to be worth booking the sleeper (which ends up being about double the rate compared to the bus ride), and sleeping in the open cabin can be a bit of a challenge. That, and the roads are at least capable of allowing for some routing around, unlike Amtrak which frequently hits freight traffic and has a pretty abysmal on-time reputation for the Coast Starlight.
Not all of us are in a rush, and most of us could use a good night of unplugged sleep. Plus it shaves off a night in a hotel, so there's actual savings there too.