Help! I've just moved house which has a pair of round-shaped security lights on the wall outside to light up my back garden. I don't know and can't see a makers name either. The bulbs have gone and need replacing. All I know is that they are G9 bulbs and I've been told to replace with either 40W or 60W but I'm not sure which to choose - I want a bright light but nothing which would disturb the neighbours or light up the whole street! Advice much appreciated.