Loud and crowded.
I liked Cambodia. I really did. It's cheap, exotic, safe, and exciting. BUT... there are people and noise everywhere. It's a very densely populated country, with lots of traffic, and the roar of society is omnipresent. Motorbikes are everywhere, even forest paths, locals play loud music all night, TVs are always on and at high volume, and it's difficult to find any type of peace. Don't be disillusioned that this is some peaceful Buddhist nation. It's not. It's a land where monks play games on their cell phones, where teenage mothers sell durian, where old men beat water buffalos, and where rice is king. Exciting to say the least.
I crossed Cambodia on my bike over a week during my Global Cycling Tour. I chose to not visit the over-touristed Angkor Wat, and instead went through many un-touristed villages in the south of the country, and tried to hang out with as many locals as possible. Many people in Cambodia just see you as an opportunity to make money, but there are certainly a few that will proudly show you their interesting nation.