I prefer SuperShuttle myself. I used
Disneyland Express once in 2009 and it added at least 30 minutes to each way compared to when I have used SuperShuttle.
DL Express picks you up and then make multiple stops around the airport. It then goes to the DLH and takes everyone's money or vouchers. After that they start taking people to their hotels.
On the way back it is in reverse. They pick you up, take you to the DLH transfer you and your luggage to the LAX bus and then take you to the airport.