This was a three night trip in January 2016. I travelled via Eurostar and Thalys in both directions, and stayed at the Cornedon Vitality hotel near Lelylaan station in south Amsterdam.
Click on the links for information about each leg of the trip :
London to Amsterdam – Eurostar to Brussels then Thalys train to Amsterdam
Amsterdam – three nights at the Corendon Vitality hotel
Amsterdam to London – via Thalys and Eurostar