Forget it.
We've just come back from Efteling in Holland.
Converted £40 Tesco vouchers into £160 worth of chunnel crossing, so only had to pay petrol to travel there. Lots of nice accommodation near by (we stayed in their holiday village - which was really good fun - but it would clearly be cheaper to stay off site).
Charm coming out of every corner. All the staff speak English, and if you get chatting to them they all seem to have stories about coming to Efteling when they were kids themselves. We stayed four days, and virtually every single person that served us seemed to really take pride in the place.
The longest we waited for any ride was an hour - but much less if you went in the mornings - so we scheduled our day accordingly. Proper loop the loopers, spooky pirate rollercoasters, 'worlds biggest wooden rollercoaster'.
Where they really outdid themselves was in catering for the under 5s. Lots and lots of themed areas where they could explore. This is so much more restful with younger children than queuing for rides.
I can go on and on about what a nice place it is! For example, the catering: one evening we ate in a pasta restaurant with a soft play attached 'PandaDroom'. About 10Euro for adult pasta and 7Euro for a kids pasta & drink. Not cheap - but not dreadful for freshly made theme park food. Then a charming extra: if the kids bring clean plates back to the counter, they're exchanged for clean souvenir melamine bowls. They're doing their own gift shop out of business!
Then another night we paid more - I think maybe 20Euros per head for the adults. This was a restaurant attached to their live show. This got you a roast chicken and vegetables in the middle of the table, a bottle of wine on the table, various salami type nibble, a kids entertainer who took the kids off and organised them to sing songs to give the grown ups a break earn their supper. Lovely atmosphere, good food with the kids occupied, overlooking the show setting up.
Until my children are old enough to go by themselves - I just can't be bothered with the cynicism and aggravation of the Merlin attractions. Dutch charm all the way for me.