I've had nearly the identical experience with it on all counts. By and large, I am a huge and loyal user of it as well.
It seems I've had the most changes in fare price or availability when identifying flights on United specifically, more so than any other airline, in my experience. That being said, it's still pretty infrequent given the volume of airfare we've booked through it for our people over the last 2 years or so.
Another thing I would add is that in connecting flight situations, it will occasionally present an itinerary that's technically possible to make, but not always entirely practical or ideal. (e.g. the window between flights is really narrow, not leaving much margin of error for flight delays, getting to another gate/terminal, etc., if not near the one you arrive at.)
All that being said, it really does work pretty great and we prefer using it to any of the other travel sites.
I would love to know why there are occasional fare discrepancies though... as far as I know google treats the click-through to the carriers' sites like an ad click, so I don't think Google is "marking it up," rather, the carriers are in some cases pricing based on the referer link or something. It can also be a demand pricing issue too, as the flight fills up, I suppose. My understanding is that Google is basically just the informational conduit between the user and the airline so it's weird that there are occasional price discrepancies.
Short answer re price discrepancies: it's complicated. It's absolutely in our interest and the airlines' interest to get pricing 100% right, and we do work really hard to eval and improve on this.
One situation that can happen is that an airline has, say, 3 seats remaining at one fare and 1 seat remaining at a cheaper fare; when you selected the flights or immediately before, that 1 seat was still available, but by the time you click through, it's not, so you get the pricing for the fare with 3 seats left.
One of the things that's amazed me in my flights education after joining the team is just how super-dynamic pricing is.
No, to my knowledge it's not based on your referrer or cookies or anything like that ;). I'm just talking -- person-independent -- pricing from hour to hour.
On a related note, I used to think that airline pricing was pretty capricious and random; now I realize that the airlines hire some of the smartest folks to develop pricing strategies, and nothing is left to chance ;).
It seems I've had the most changes in fare price or availability when identifying flights on United specifically, more so than any other airline, in my experience. That being said, it's still pretty infrequent given the volume of airfare we've booked through it for our people over the last 2 years or so.
Another thing I would add is that in connecting flight situations, it will occasionally present an itinerary that's technically possible to make, but not always entirely practical or ideal. (e.g. the window between flights is really narrow, not leaving much margin of error for flight delays, getting to another gate/terminal, etc., if not near the one you arrive at.)
All that being said, it really does work pretty great and we prefer using it to any of the other travel sites.
I would love to know why there are occasional fare discrepancies though... as far as I know google treats the click-through to the carriers' sites like an ad click, so I don't think Google is "marking it up," rather, the carriers are in some cases pricing based on the referer link or something. It can also be a demand pricing issue too, as the flight fills up, I suppose. My understanding is that Google is basically just the informational conduit between the user and the airline so it's weird that there are occasional price discrepancies.