What colour should i dye my hair and will it fade quickly?

I'm mixed raced so i have medium brown skin and my hair is dark brown/black and my eyes are the same my hair is naturally afro but i have relaxed it so its straightish but still really thick and i plan to dye it red or purple but i would prefer red but don't know what would like nicer? before i dye it i will prelighten it with two kits of B blond powder bleach from super drug and then plan to die it with Schwarzkopf Live Colour XXL Red Passion R43 two kits or Live Colour XXL Plum 47 two kits but what would look the best and would the colour fade quickly?