I've had my rinsekit for 4 years and have had zero problems. The relatively inexpensive Amazon pressure sprayer looks like a good solution, too. The main advantage of the rinsekit is that you can pressurize it from your home tap instead of pumping. I've had no problems with it maintaining pressure, although I did get the pump accessory for when I'm away from pressurized water. The cutoff valves, hose, quick connects, and sprayer are also top-notch which add to the cost.

Value is in the eye of the beholder, for me it's been a good investment when I amortize it out across all the trips it's helped out on.