I was always really against using any kind of nit treatment on DD and always went down the condition and comb (for hours and hours) route, until CountessDracula and bundle mentioned Hedrin on MN.
I didn't like nit treatments because of all the chemicals, and the fact that they were labelled unsuitable for asthmatics. DD is not asthmatic but it made me wonder what was in them and I didn't want her inhaling it (and they STINK and are expensive).
It seems though that Hedrin is different and you do not absorb any chemicals from it, it just smothers the nits and makes your hair too slippery for them to cling to.
She has very long thick hair and it was becoming more and more of a pita to be constantly combing when she had got nits, she could be made to sit still for almost an hour while I combed through it all, every 2-3 days for 2-3 weeks.
So I tried hedrin the other day. Amazingly it does seem to work, there were loads of little dead critters on her pillow in the morning. We still need to do the 1 week later treatment in a couple of days (which I think is what a lot of people forget/don't realise), but it does seem to have killed LOADS of them (all the ones we combed out were dead). It doesn't smell at all, and just seems like a gloopy conditioner (although you do have to wash it out very well). The only downside for us was that we had to use an entire 'family size' bottle (£12 ish IIRC) for DD's long hair, which means after we've done the second treatment I'll have spent £25 getting rid of the little buggers <grumble grumble>
I think I will still be check regularly with the nit comb though <paranoid>
So thanks to CD and bundle for the recommendation!