I've used them and others - they are all reliable and punctual - and typically will understand english and take credit cards - and also ask you if you want to take highway (faster but toll's are more expensive). I used a service yesterday to pick me up at 6am to head to HND for my 8am flight.

FYI - you can also take a taxi by just walking down stairs after you clear customs - follow the signs to the taxis it's really easy. The first taxi's you will see are typically "long drive taxi's" - if youask them to go to just Minato-ku they will point to the back of the line - keep walking and you will see the normal ones in line behind them.... All of them are nice and to be honest it's quick and easy and completely safe. To give you an idea of the taxi cost for me to get to my area of Minato-ku (Hatchobori) on the highway costs me about 6,000 yen and takes about 20 minutes. To your hotel it may be slightly less.