In previous threads, we discussed the National Express
dot2dot shared van service as a potential alternative to the HEX or the Underground as methods of making the journey to and from the airport directly to your central London destination. I wanted to share my positive experiences from a few days ago:
I had pre-reserved a return journey, for the cost of GBP 30.40 (USD 48.19 at today's exchange rate). This price reflects the October 2008 20% discounted price of GBP 16 instead of GBP 20)**, plus the additional 5% discount for booking a return journey.
I had reserved my outgoing trip factoring my arrival time, plus some time to use BA's Galleries Arrivals lounge in T5. Because of ahead-of-schedue arrival, I was ready to go one hour before my reserved time. I approached the desk in the T5 International Arrivals area, and was told that there would be no problem getting me on an earlier shuttle. After a few taps on the keyboard, one of the staff people walked me and two other customers out to the curbside, where the van (a newish-looking Mercedes vehicle) was just pulling up. After the bags were loaded, we proceeded over to T2, however, the expected passenger was found to have gone on an earlier shuttle, so we proceeded into the center city.
The van's interior has plush leather high-backed seating, with shoulder-type seatbelts for each passenger. Each seat has a reading light with on/off switch overhead, and the back rows are arranged around tables. There is a power outlet in these rows, marked for laptop and mobile phone use only.
The inbound driver was very courteous, but had a bit of difficulty in his routing (I was the third of the three stops). He missed his turn at a couple of points, needing to back up and change direction, but this did not add more than a minute or two to the overall time. The only bad part was that the midday traffic was heavy, with construction delays slowing us down. However, I was at the hotel's front entrance in just about one hour from departure from LHR t5.
On the return trip, the driver (again courteous) actually arrived about 10 minutes early. We had no navigational difficulties,

and we made it to LHR T1 in exactly 35 minutes (with a stop at T4 before mine at T1).
In short, dot2dot provides a viable, moderate-cost alternative to the traditional airport-city center transport options. The door-to-door concept eliminates the need for a second fare (for example, although the HEX fare is normally GBP 16.50 (less than d2d's non-discounted fare), unles you are staying at the Hilton Paddington or very close by, you would have to take a taxi or the tube to your hotel).
d2d can be especially usefil in a situation like on the morning of my return, when the rains came - consider the difference between schlepping in the rain to a tube or bus stop at 4:00 am, as opposed to being picked up at the entrance to your hotel. With its new rolling stock and courteous employees, I feel comfortable giving dot2dot a high recommendation.
** The 20% special is for trips booked by October 31st, and taken by Christmas.