Just got back from LOS yesterday or this morning - confused.
Went on the oriental river cruise after the suggetion above and it was very good. Good food, the guide who I could not work out his nationality was good and we all had a good time.
Only downside was the bottle of wine I choose got subtituted for a different one which I did not mind but I was not told it was 400 bht more. Add on to this the service charge and VAT which I also did not realise and my wine cost over 800 bht more than it appeared.