We visited Holiday Park and water park on a Sunday, which is supposed to be less crowded than Saturdays. It was in the 90's and very humid and VERY crowded. Waits for rides were about an hour, and in that weather, just about impossible to tolerate, so we went on very few. we were disappointed to spend that much and not go on many rides.
The holiday themes are weakly presented and much more could be done with them, to give the park a more unique quality.
We have been to many amusement parks, and the big plus here are the free drinks and free sunscreen included in the ticket price. It shows that the park cares about its' guests not getting burned or dehydrated, and was a valued feature to us. We were also pleased that food prices were average and not inflated, as they are at every other amusement park we have been to.
In general, I would recommend the park ONLY if you go on a weekday, when hopefully the crowds would not be as bad, or in a slower part of the season.