FFMPEG terrible conversion quality when using -sameq (same quantizer as source) flag

I'm trying to convert .flv videos to .ogg format. After experimenting for a while, the ogg is always produced as very low quality. Even when I use the -sameq flag which uses the same quantizer as the input file, the quality is substantially worse.

Since I am pretty new with ffmpeg, does anyone know some good options to convert video files with maximum quality?