Probably my lack of cultural interest, but I thought the Wat was boring after 20 minutes. Like most temples or cathedral, just seems to be repetitive.
Siem Reap has other interesting things to do the best time I had was renting an ATV and cruising off road.
Pub street, cheap massage, good food and some ladies there to date if you are single.
3 days there is about right, but a 3 day Wat pass seems like a waste.