How bad for your hair is it. I would only top it up at the roots rather than do the whole head.

How damaging are those semi perm colours also, I have been using a permanent colour through my whole hair and its started to break off.

Thanks.

i asked my hairdresser about sun-in and products like that and she said that they're really horrible for your hair. she said it's much less damaging to just get it colored normally.
semi-permanent aren't that damaging for your hair...
if you're just trying to go darker, i recommend a deposit only color, so that there isn't any bleaching.

Thought so, thanks for that info

Semi-permanent colors are actually GOOD for your hair since it is not penetrating the shaft and only putting it on the outer layer. It's like a coating for your hair. When my hair was getting dry I dyed it darker wtih semi-permanent color and it filled in the holes and made it SOO soft! The bad part is that they won't lighten your hair.. you can use them to darken or brighten though.