Well, we are just back from a weekend at Legoland and overnight stay in a hotel and ds1 was an absolute star all weekend. So much so that we didn't need to get an exit pass - although to be fair he didn't have to wait longer than 30 minutes for any of the rides he wanted to go on.
After we arrived and he'd been on the Viking Splash and Spinning Spiders he seemed to suddenly become, well er, more visibly autistic for a while and seemed quite out of sorts and very pale. He was spacey, started tic-ing and being non-responsive when we spoke to him and dh and I thought 'uh-oh, this was obviously a bad idea and may have to be cut short'. So, we did a few quieter things, had a picnic and let him and his brother go in the childrens adventure playground, but he seemed to get worse - wandering around and around in circles and really just being not quite there. 
Dh said to me that if we were going to have to leave, he would like to go on the rollercoaster first and asked ds1 if he'd like to go on too. He wasn't sure, but said he'd have a look. He didn't like the look of the Dragon but decided to brave the Dragon's Apprentice. Well, one trip around on a rollercoaster and it was as if he suddenly snapped out of it and came back to us! 
I suppose it must have been the adrenaline?
He coped well with the hotel. (We booked one of those apartments with a bedroom for us, sitting/bedroom for the dcs, kitchen and bathroom.) Fortunately, the hotel had set the boy's beds out in the same position as their beds in their own room at home and ds had bought a new Lego DS game with his birthday money, so he settled right in and made himself at home. We kept the bedtime routine the same and brought food from home to cook, so it was at least a facsimile of his routine and I think that helped.
Unfortunately, he was the same again on arrival at the park this morning - ok for about 15 minutes, then a rapid decline once we got in. It was much busier today and he did get overloaded, but handled it so well.
Not one meltdown, not even a tantrum for the whole weekend. Just some very sad tears before we left and in the car on the way home because he had had such a lovely time and was sad to be leaving.
He also came to me before bed and said "Mummy I have had the best weekend I've ever had in my life and I really want to thank you for taking me to Legoland". 
So formal, I had to smile, but sooo lovely as well, bless him.
Dh and I are so proud of him for coping so well and managing to cope with being overloaded and get through a whole weekend of disruption.
Amazingly, I managed to survive it all as well. Dh went on all the rides with the dcs (bar a couple of gentle ones I did with dd) and I did have to spend an awful lot of time resting and sitting around on benches, but I coped and that's a huge improvement on my energy levels over the past few weeks - especially when a fortnight or so ago we thought we might have to cancel because of my health. I will pay for it this week - but it will definitely have been worth it.