if you can master the tower trainer then there is no reason to buy another trainer which is faster and heavier. the four star will land at similar to slightly slower then the duraplane and you will have more enjoyment from it. I see no need to relearn the skills you have just mastered on the tower trainer. No matter what plane you buy you will crash when you start to think you know what you are doing because the planes have a tendency to remind you of what you do not know.