hot water dispenser

Any one use the under sink hot water dispensers, commonly known as In sink-erator, they also make disposals and such. What has been the life of the units? I installed one about 4 years ago, and now its started to leak at the water inlet on top, its a push in type fitting, and looks like a small diameter PEX tubing there. the clamp that holds the tube in place broke, and now its not holding too well and when you turn the knob on top, water leaks from the fitting, I am wondering is it worth the trouble to find this part, and see if it works, or just replace it and be done with it. They are a great device to have next to the sink. Thanks