Fiona N
Veteran
As the owner of some old (halogen) Lumicycles (I think ~12w on my helmet)...
Me too - I ride unlit country lanes around here with a 7w or 12w 'spot' without any problems seeing where I'm going or blinding oncoming drivers. Most of the time, the drivers do manage to dip their headlights but just occasionally there's one who you don't know whether is fully compos mentis and for those situation, I find the 20w 'flood' does tend to wake them up but as it's a wide angle it's 'dazzle potential' is quite low.
I recently bought a Lumicycle 5 LED light for overnight Audaxes as the battery life is better and that is crazily bright on full beam - I can easily ride with it on lowest level (of 4) without any worries.
So far when I've been out and about either on bike or driving, the only bike light I've had problems with (on an approaching bike, that is) was a guy with a powerful LED headlight on flash despite it being fully dark (and 4am) - it was also aimed firmly at oncoming traffic - high and focussed rightwards not straight ahead. As I got closer I could see that he had a much weaker light actually pointed at the road. This sort of behaviour strikes me as being just completely unnecessarily aggressive.