I visited this site after I visited Angkor, which in hindsight may not have been the best idea, as no other set of ruins in the area can compare to it. However, it is a nice site and deserves a visit. I particularly enjoyed the buddha statue that got entwined with the tree roots. It is also relatively crowd-free, at least on the day that I was there. These temples are in true ruins (unlike angkor, which is very much reconstructed) and offers a different atmosphere. 

However, like others have stated, what UNESCO chose to include and exclude from the site area is a bit confusing. Some of the most notable temples were not included within the site. Also, the city around the ruins is not that pleasant, and there were people riding elephants in the vicinity, which I find unethical. 

Overall I found this worth a visit, but perhaps in a visit leading up to Angkor to avoid comparisons.