I used Monokote when I first started in the hobby 15 years ago. I then switched to Ultrakote because it was easier to use and didn't sag. Sadly they discontinued it, when it first came back on the market I bought some, it was definetly not the same quality. I helped someone build a plane a couple years ago, and he had bought Ultrakote, I was amazed that they had returned to the original quality. I have been using it exclusively since.