SL - the post-Mara celebrations are Amsterdam are ace! I did it in 2011 and finished the race at circa 12:30pm, where I was promptly dispatched by another member of our group to go and buy some water and a cup of tea. By some amazing turn of events I returned some 5 minutes with later with 12 pints of Heineken (and a cup of tea obviously). This somewhat set the scene. It was a friend's birthday that day. Debut Mara and someone then produced a bottle of Moet. This was supped sitting in glorious sunshine in the Olympic stadium awaiting the finish of the Half (where we had 3 runners competing). I believe 12 more pints of Heineken magically appeared too, although I'm not sure how.
The evening followed a very similar pattern. I had my first ever taste of a truly delightful beverage known as Jagermeister. This has the uncanny ability to make you lose all control of your lower limbs, so I spent several hours walking in a Shakin' Stevens style. After a few more of these 'Jagerbombs' and 3 verses of Green Door I found myself throwing some impressive shapes on the dancefloor of a discotheque in the red-light area. The locals were amazed, and they stood pointing at me and staring at disbelief at the superb moves I was able to execute.
In the end there were just the two of us still standing - me and my best mate (who had ran a 2'48 PB during the race). We eventually got kicked out at 4:30am and got a taxi back to our hotel. This was particularly memorable since we could only just scrape together enough loose change to pay the fare - and this despite going out with over €400 between us. Don't EVER tell Mrs LS21 that though......
The next day was a true joy as you can imagine. On trying to put my shoes on I fell forwards off the bed and went head-first into the TV. And then couldn't get up. I felt slightly worse for wear it must be said, and even missed the free breakfast.
So if you do go don't eat at an Italian restaurant near some big shops as we did. My sudden post-Marathon illness was caused by a dodgy mushroom on my pizza, and I'd hate you to experience a similar feeling of woe and general malaise. Still, the outstanding customer service and general unbridled joy exhibited by the Ryainar team made the weekend worthwhile, so a risk worth taking perhaps.
Anyway, that aside it's a quick course and a cracking weekend away, so give it a whirl.