V
Vitesse
12 is too many on a V Pro dimmer switch it will fail eventually. I know from experience. The maximum recommended by Varilight is 10 bulbs even though that is less than the 120W rating. I spoke to Varilight and they explained that they recommend only 10 x GU10 LED's max due to inrush when they are first switched on. You need to fit a V Com dimmer switch that can handle up to 20 x GU10 LED's rated at 180W. TLC sell them if you have one near you?