Probably a stupid question, sorry, but I'm rubbish with colours and have worn some pretty dodgy combinations in the past. 
I want to buy a warm hat and gloves as my hands are constantly freezing. My winter coats are mostly black or navy, with one olive green jacket. I'm looking at knitted hat and glove sets that come in olive green, navy, or stone/oatmeal colour. Which would be most versatile, do you think? I presume not navy, as I can't wear that with a black coat - so olive green or oatmeal? Which would you get? Will be hoping to have these for years, so don't want to regret the colour.