I am not saying not to use these companies but please be aware of what can go wrong if the timing of your trip is critical:
Using Orbitz I purchased a RT Tijuana to Quito on LAN Chile. Two days before the April 28, 2012 departure I received a routine e-mail reminder from Orbitz. I noticed the middle of the three return segments was commencing prior to the first. Obviously an impossible schedule.
I immediately called Orbitz and after a while was told to call back in the morning. I did and they finally told me they had "fixed" the problem by moving the other two segments back one day. I did not want to loose a day of my already short trip but it was too late at that point I was told.
I arrived at the Tijuana airport 2.5 hours early and was told that I had to pay a change fee by Aero Mexico - the operator of the LAN flight. I politely protested but agreed to pay it. I got shuffled around to two different windows but neither could process the fee due to LAN being closed on a Saturday. The Aero Mex staff worked very hard to get me on that flight but the clocked ticked down and ultimately they could not let me board.
I returned home to San Diego and called Orbitz. They also could not do anything due to the weekend and told me to call back later. I asked if they could work on rescheduling and they took down some possible dates from me and said they would look into it. I have been calling them over the past several days, each time having to explain myself and finally getting transferred to the international staff. There is no direct line to international.
So far all I have been told is that LAN is denying a refund except for unused taxes. After four days Orbitz has pledged to refund my fare minus any taxes that LAN refunds. Orbitz has also offered me a $100 travel voucher. That is a good start but not quite enough in my opinion to compensate for all the inconvenience.
I blame LAN for making the idiotic schedule change but fault Orbitz for not having their computers programmed to catch the error. I blame both for not being available at the critical time when, despite my outbound flight being error free, I was not allowed to board. Everyone lost. MY trip was ruined and three segments that day had an empty seat. It is also very unsettling that neither company was willing to put a person on this fiasco right away and see it through. I am on my own. Luckily I am fighting this from the comfort of my home and not from some airport hotel in a strange city. This situation could have been a lot worse is what I keep telling myself.
UPDATE DAY 5: I was just contacted by Orbitz. They were told by LAN that I could not board due to "visa issues" and they (Orbitz) have rescinded their offer for a full refund. They upped their voucher offer to $200 and said that LAN would be refunding $99.86 in taxes.
Ecuador does not require a pre issued visa for US citizens and my passport is up to date. Not sure why LAN would make that up but I am very disappointed in Orbitz for just accepting it. From the time this happened I have been treated like I had done something wrong and now it is implied that I am a liar.