Travelling Cambodia is rather easy for overlanders and people are quite friendly. Visa-upon-arrival 30 US$ for 30 days, Carnet de Passage actually required, otherwise vehicle import quite expensive and time consuming. Some extra US$ for “quicker” procedure. At some borders CdP is not signed because they do not know how to do it, don’t insist but forget about it. No poblem when exiting. Just home driving license and vehicle documents. The total entry/exit process requires not more than 30 minutes at border including customs, no inspection, no need for Cambodia driving license nor car insurance, just relaxed friendly people.
Road conditions quite good but beware of all the mopeds, bikers, cows, chicken and people and of night driving. Cambodians drive extremely passive, not surprising, and will never stick to any rule in general. Mines a problem all over Cambodia, better forget off-road driving or camping. Diesel 50 Euro cents/l but much more in Phnom Penh or Siem Reap. Toll on some bridges, no road toll, reasonable entrance fees.
People in general are quite friendly with overlanders and interested in them and like to take photos, but in tourist areas like Vientiane and Siem Reap they will rip you off anyway. Beware, younger girls get crazy about “Farangs”.