Motability cars?

I've had a few crappy little runarounds since getting my licence and feels like I'm just throwing money away now with it. It's also very painful to drive my current car, I need something a bit bigger as even on furthest back setting the seat is too close to the pedals so whatever happens I need to replace this car.

I've got the possibility if getting a Motability car but I know almost nothing about the scheme other than they take the mobility payment in exchange for a new car which includes just about everything.

Does anyone know if its worth going with the scheme? And how to pick out a suitable car? I'm lost with the whole idea!

Thanks