I have very red hair.
Pic on profile.
Its lovely. I love it. Everyone else loves it. you dont know how many compliments you get having hair that colour. People have stopped me in the street.
Its fantastic.
It took about 3 goes at the hairdresser to get the colour in my pic. ( so 3 months)
Here is the downside.
It fades like crazy. Within a week it looks nothing like the same.
The red comes out when you wash it and leaves your bathroom looking like a scene from texas chain saw masarce.
I have got my hairdresser to get me some salon dye, which, as she knows me, she lets me take home.
I need to redo it every week. It still fades to a chestnut colour within 4-5 weeks.
You get BAD roots. ( like people with dyed blonde hair get)
If you can accept that its going to be really high maintence, quite costly, and WILL fade, then go for it.
If those things will bug you, then dont.
Also, once you have got fed up with it, whatever colour you have on top, it will fade and the red will keep coming though for ages and ages ( depending on your lenght of hair and how often you have it coloured) but about a year if you have long hair and are having it coloured once every 6 weeks.
BUT - all the bad points for me, do not outweigh the good.
It would look awesome i bet.