If you put your reg into blackcircles it will tell you the speed rating, and V and W come up as acceptable.
I have always fitted W rating to my 180, the only thing I have to say is I had 2 infinity tyres on the front before fitting Kumho le Sport tyres all round, and I had ever felt so unsafe, the traction was shocking, I found them dangerous in the wet
The Kumho however are amazing, 4 fully fitted cost me £322.00