We stayed at Sans End from early May to late November, and had a great time.
There are some shady spots, if you can can get them its well worth it! Of course the summer months are hot, but what do you expect, its Yuma lol. Once mid September hits the weather cools off at night and its a lot nicer.
RV sites are decently spaced, we had enough space for a 35 foot 5th wheel, our F350 truck, and a commuter car.
Laundry facility had a lot of machines, we never had to wait for one to be available. Same with the showers, though Im not a fan of coin operated showers in general. They were spacious and clean, with shower chairs provided for those who need it.
Everyone at the front office is super friendly and helpful, they do a good job at keeping the park clean. They even have a truck go around to douse the main paths with water to keep the dust down.
The dog parks are spacious, with some creative tire obstacles, and they are well stocked with doggy bags, its the ideal setup for pups. We've traveled a lot over the past few years and this doggy park is a standout.
Overall this is a really good RV park to stay at, if we return to the Yuma / Winterhaven area we will be back!