we camped at nason's creek recently, mid June. Unfortunately for us the weather was not warm at all and was actually pretty cold and stormy. The lows were around 40s and the highs were 50s. Bummer because I wanted to get my feet in the creek! We camped at site 44, just across from the creek and we were nearest to the bathrooms. The bathrooms are stocked with toilet paper but no hand soap. There is a powerful dryer in there. Outlets as well. For 4 people, the campsite was pretty small. We also had three dogs so maybe that was it as well. It would be perfect for a couple and one or two dogs but as far as group camping I would have liked a bigger site, even though the sizes of the sites are not listed. The camp trooper came around making sure we all had our food packed away as there was a bear who had a feast a few campsites down. He was very friendly and knowledgeable about everything in the area. It is only 30 ish mins from Leavenworth, so we visited there as well. You are only 10 mins away from lake Wenatchee if you are looking for swimming. You need a discover pass which you can purchase a day pass there at lake Wenatchee if you do not have it. It is not required for nason.
I would recommend staying here. We did not experience any mosquitos or bugs. It's a perfect quiet hidden gem. Looking to go again soon!