It’s true that there is a direct bus from Sihanoukville to Siem Reap (where Angkor Wat is).
It is also true that when you are making reservations for this bus, that the travel agent will tell you anything you want to hear.
When we asked if the 14 hour night bus from Sihanoukville to Siem Reap had air conditioning, we were told that it did. IT DID NOT.
When we asked if the bus we would be on would have a toilet, we were told that it would. IT DID NOT.
Unfortunately for us, we took the “sleeper” bus.
If I had to do it over again, and I really hope I don’t, I would take the day bus. At least then you can see what you’re getting before you get on.
What we got were seats made from molded plastic that were built for someone about 5’2”. They were permanently reclined, and at an angle.
So, 180 degrees flat from feet to waist, and then about 145 degrees.
I know what you’re thinking. You’re thinking “That doesn’t sound too bad.”
But remember no AC (and it’s about 90F outside), and no toilet. For 14 hours.