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Some good points, not sure about NDB though. I don't consider this to be an important approach to master on EFT at all! Better to get handling skills sorted and some basic understanding of IF work prior to BFJT - without a doubt, the Grob's instrument suite provides this!
Your point about aeros is also a little misguiding - the skill with aeros on a more powerful machine remains the same; working to a base height requires throttle management so you don't climb and come out of each manoevre at the correct speed - think about the Tucano/Hawk!
I think the Grob is probably a better EFT machine, but it does look like a motor glider (unlike the mighty bulldog!)