1

Taxi Green has a counter with a big board with their prices after you pass through the glass sliding doors after having gone through customs. They have a counter and price board also at national arrivals right in front of you when you leave the luggage pick up area. On those boards they have listed their prices by district, including Miraflores. The best thing is to go to one of their counters and check the price list and check with the young lady at the counter what will be charged. And then confirm it with the driver. Ignore all drivers who will approach you upon your arrival, whether they are or say to be Taxi Green or not. Go to a Taxi Green counter. There is no price difference between day and night. There are unannounced price increases at special times, such as Christmas.
Taxi Green is a fairly loose combination of taxi drivers which is recommended by the airport with the purpose to provide safety. However, that does not necessarily mean that individual drivers strictly adhere to the stated prices and don't try to get more money out of you. Chances are that such drivers upon arrival will ask for a tip, although tipping taxis is not customary in Peru. Make sure that you agree upon the price in soles, not in US$.
The way I know Taxi Green (I don´t use them myself, but I see them in operation) it does not surprise me that they don´t reply to your e-mails about current prices.
I believe that their stated rate to Miraflores is about 50 soles.

2

Beleive we paid 40 soles last month--it is a fixed charge as stated on their board.

3

I hit Miraflores Lima a couple of nights ago and I must have gotten taken. My charge was 75 soles on a credit card. Exhausted from finally getting off the flight at 1am, I didn't see any board with any prices and there were a couple of guys arguing over taking me. I settled on the cheapest one.

Now that I'm here I realize that is way overpriced for the area. The exchange is about 1 USD - 2.6 PEN, which came to about $28.50 USD. I spent double that getting to the airport from Manhattan, so I don't feel too bad. It was a nice drive through Lima and the cab driver was very engaging.

Miraflores is beautiful. I walked the "beach" (huge, smooth rocks, and no sand) yesterday and watched the surfers and paragliders. The views above the beach line are gorgeous. This is a great city to be in for the next two weeks.

4

Numimuos7: It does not matter now, but the board is there, AFTER PASSING THROUGH SLIDING DOORS WHICH ARE AFTER PASSING THROUGH CUSTOMS. To the right. Before those sliding doors there are some more expensive agencies. The problem anyway with arrival at Lima airport is that one will be acosted by several taxi drivers. But if one ignores those and is intent on using Taxi Green, one will find their counter to the right after passing through the glass sliding doors (international arrivals).
That is, if one wants to use Taxi Green. Some people who regularly arrive at Lima airport and know the way walk to the street and take a taxi there. Sometimes arranging a pick up by your hostel may work out cheaper then taking a taxi yourself.
Would you leave the airport building, immediately outside you will meet the real sharks. Taxi Green was formed a good number of years ago to give the opportunity to avoid those.
I guess that using a credit card for the taxi you place yourself in a more expensive category anyway. It would be more economical to get Peruvian soles, which can be done already when waiting for your luggage to arrive, and pay cash.

5

When I was there in June, the price to Miraflores was 45 S. The prices will be a fixed rate and clearly stated on their board as others above have mentioned.