I like to have cases for all my gear, and I tend to use 'soft' cases (as I no longer drive a van, and hard cases tend to damage the inside of cars!)
I was a little concerned about how well protected my keyboard would be in a soft case, but I was pleasantly surprised.
I'm not sure what is in the case, but it is reinforced by either (very) thick cardboard or possibly thin wood - especially around the edges. You obviously couldn't drop a solid case on top of it (layed flat) and expect the keyboard to survive, but the solid sides offer excellent protection; both in the car, and when putting down (or even dropping?) on the ground.
If you're clumsy, or (your roadie is) throwing all you gear in a van then you need a flight case. If you pack and carry your keyboard, then this a much more than a 'padded bag' and offers far more protection than you might expect. I'm really pleased with this one.