Maybe it's cheaper because no one wants to go there. I personally can't imagine skipping Angkor. It's one of the wonders of the world! Rangoon/Yangon sounds nice & I'm sure the pagodas are cool, but it's nothing in scale like Angkor. To me, a few hundred bucks is negligible compared to the overall cost of the trip & the experience of being there. Plus the [gay] Linga Bar in Siem Reap makes the best mixed drinks I've had in SE Asia.

David