I have a TomTom ONE Classic Regional and had left it in the glove compartment with the rear mount attached. Because it was loose the suction cup that fixes it to the window was damaged and we had to buy another one - and they're not cheap. So to avoid the same thing happening again I bought this case.
My TomTom fits perfectly, and the screen protector flap is great. It's necessary because you can fit so much in the other side of the case. Currently I have my TomTom, the rear suction cup mount and the charger all tucked away in it.
If you are looking for a compact case, this is not it. It's quite large and won't just drop in your hand bag or be discrete to carry when you take it out of the car.
That being said I would thoroughly recommend this product as it does exactly what I want it to, keeps the TomTom protected and keeps all the paraphernalia that goes with it in the same place.