I used Amin Tours to arrange for a short Golden Triangle tour. The driver provided was very polite and helpful for the entire trip. He picked me up at my hotel in Delhi in the early AM and drove me to Jaipur, where we met up with my tour guide. We went to see the Wind Palace, City Palace, Jantar Mantar, and Amber Fort. The next day, my driver took me to Agra where I was able to see the Taj Mahal (again, a tour guide was provided).
Overall, the trip was excellent, especially for the money. The amount I paid for Delhi -> Jaipur -> Agra -> Delhi was less than what other tour companies were asking for just Delhi -> Agra -> Delhi.