I will have 2 to 3 three days for beach during trip to Cambodia , at first I was thinking of going to Sihanoukville. But, after reading The Internet, which says that it's a very unsafe town full of drunk and wasted people who spend time with whores, I began to have doubts. Maybe you can recommend some other place, which would be more quiet? Or everything is too exaggerated and it's a totally safe and normal beach party town?
However, apparently there are various parts of the Sihanoukville area - some quieter than others, so hopefully somebody else on the forum can give you more information. From Kep you can take a trip to Rabbit Island for the day which has some nice beaches. Take a look at Otres 2, certainly didn't see any of things you mention and we were there for 12 nights.
We are heading to Cambodia in 42 days time not that I'm counting Not being interested in the "drunk and wasted" type place either, we went looking for quieter, more remote places, and have booked Monkey Maya which is between Sihanoukville and Kampot. Google it and see if it's somewhere you might like too. Also some of the islands off Sihanoukville seem to be quieter than the mainland and have some nice beaches.
Koh Rong Samloen looked less developed than Koh Rong. Another one is Koh Ta Kiev. Yes Occheuteal beach is aimed at the younger, party crew and over the high season can be a very "vibrant" and "colourful" area! However, the western end, which is known as Serendipity Beach , is completely different. A LOT more laid back. The noise from Occheuteal bars can be a problem early in the morning though. So that leaves you Independence beach , which is beautiful and quiet.
Victory beach, which unfortunately isn't a shade of what it used to be, Sokha , which is definitely the pick of the beaches, but is a quasi private beach mainly for those staying in the Sokha resort, then on the other side of Occheuteal, Otres1 which is a mixture of party and chill and Otres 2 which is beautiful and tranquil.
