Having caught and eaten many mice, I would say that they all taste sort of piquant but with a touch of a grassy aftertaste when they are outdoor mice, but they're not all the same. A healthy and active mouse has a much peppier and more vibrant taste than an unhealthy or debilitated mouse, and indoor mice sometimes taste quite dusty and unappealing. In the case of a mouse which is seriously lacking in good taste the best thing to do is decapitate it, swallow only the head, and deposit the rest at the feet of your staff ("owners") who will grumpily dispose of the remains. Pay no attention to their dramatic bitching and complaining. The truth is, they love the attention, and they admire your hunting skills.