I've used Taxis in Japan across the country for 20+ years, can attest to its quality, reliability, and professionalism. It's on the expensive side, with rides usually starting at 700 yen (roughly 7USD) [1], but the drivers are courteous professionals who drive smoothly and know their cities and routes cold (if they don't, they'll apologize for not knowing and ask you for directions).
The only downside is that sometimes the drivers are cigarette smokers. While they won't smoke inside the car, the odor can be very noticeable.
[1] I believe this will be reduced to 500 yen soon.