Bravo, Bradleyo!The proportions you give (4 parts gin to 1 part vermouth) is what I've always read was the classic formula for a martini. Most of the martinis I get in restaurants and bars have way too little vermouth. I became a fan of martinis (Gibsons, actually, which means garnishing with pickled onions instead of olives when I stopped believing that the right formula was to use next to no vermouth - usually with appropriate joking about just introducing the gin to the vermouth. I read that 4:1 was the right formula, tried it out, and discovered that the vermouth smooths out the edges of the gin and makes the drink really enjoyable. I've even tried taking the gin ratio down to 3:1 and enjoyed the result. The bitters aren't traditional, and I've never tried them, but will.