Good settings for Blu Rays in Handbrake

I'm going to start encoding Blu Rays with Handbrake in a month or so, but i was wondering, which is the best way to encode them, use constant quality or average bitrate? Depending on your answer, please say which of either you use for yours. I don't want the files to be too huge, but i do want the quality to be good that most won't notice a difference in quality. Thanks

The content will be on my Windows-based media center hooked up to a TV.