Fantastic Amantaka
First I must state, that in contrary to Chamade's report, that there is definitely no "slum" next to Amantaka. There is no slum at all at Luang Prabang - of course Laos is no rich country, but there are regular local roads and regular local houses.
Our stay at Amantaka last January was magical: The beautiful gardens, which are lit at night with thousands of candles. The fantastic cuisine, better than at most other Amans. The Never-To-Forget private boat trip down the Mekong with food, drinks and the amazing Aman host, who was born in Luang Prabang and told us - in fluent english - highly interesting facts and stories about the magic and beautiful land around the river.
I highly recommend staying there!