I always found those lights terrible. I hate working in offices that constantly have them on and get headaches much more often than in natural lights or darkness.
Typically I try and buy LED based backlit LCDs but my favourite right now are OLED based displays which seem more natural even than LEDs (less bright?).
On my work LCD (CCFL) I have it set from "100%" which is the manufacturer's default (LG) down to 30%, and still find it more than bright enough for my usages.
I honestly think manufacturers are playing a dangerous "brightness" wars game which will damage consumer's eyes in the long run with ever brighter displays being marketed every day and people getting genuinely excited that LCD X is 25% brighter than last year's model.