I can imagine a few sites being the equal of Angkor, but surely there is nothing that can better it. The sheer amount of temples would be impressive, but each one seems to be some form of new masterpiece. I spent 3 days travelling around the temples and didn’t get bored; each new one was a delight. My personal favourites were the Bayon, Preah Khan and Pre Rup (all on the Grand Circuit).
I almost missed my highlight, which was an early morning where I had Bantaey Srei all to myself. The temple was magnificent, and displayed a different batch of imagery to that which is frequently used in the central Angkorian complexes. I almost didn’t make the trip out there and it was only because I decided to go to Kbal Spean and had to be back for an early afternoon bus that I was there by myself. However it was certainly worth the trip.
I can’t really add anything more to what people have already stated here. It is well worth as much time as you can spend on it. I would recommend travelling around the sites by TukTuk as it is very affordable and gives you a better view of the sites and environment.
Outstanding, the best World Heritage Site I have visited.