I went to Amsterdam by train a couple of years ago. It was very pleasant but there were nearly six hours between my train arriving at Brussels and leaving for Amsterdam. I didn't mind so much as I'd never seen Brussels and this was in work time but if you're going away for a weekend, there's a...
I'd go by train precisely because I could work. It's pretty hard to do work on a short haul flight, there's more time queuing that sitting, but a three-hour train trip would be great for getting work done.