As a Las Vegan, I have countless fond memories of the Wet N Wild there. It was pretty much an institution for kids and teenagers in Las Vegas in the late 90's and early 2000's. Now it is closed :(
My wife and I made a road trip to Phoenix's Wet N Wild to relive some of that childhood joy. We are older now (27) but still were still excited.
I'll cut to the chase: it was still fun but the lines severely curtail your good time. We went on a weekday toward the end of summer and some lines were over a half hour. Only towards the final two hours of the day did the lines start to diminish. We determined that it was not so much the amount of people, but the lack of a proper number of larger rafts for the rides that require them. On some rides (the "red one" and the one where you go up a wall then come back down) you can go 5 minutes without seeing anyone on the slide.
All of the rides were a good time, and I wouldn't say there is a dud among them. The Constrictor does indeed have tight turns but is over too quickly. The "water coaster" ride lives up to it's billing and was the best one by far. Make sure you ride in the front of your two-person tube on that one. The ride where you fly up a wall, then practically free fall back down is a heartstopper, as is the Twister (a cone on its side).
The lockers are a bit pricey ($7/$8/$9) but are worth it since you get a wrist band which provides you access all day with no key to lose. The pizza in the restaurant was good and reasonably priced ($6 for a quarter of a pizza, plenty for two adults).
The Lazy River is useless. The Lazy River in Vegas used to allow you to get from ride to ride without walking on the scorching pavement. The Lazy River in Phoenix is a purposeless float off to the side of all the rides.
It was a good time and I'm sure kids would have a blast. For the discerning adult, it'd probably be wise to avoid weekends.