depends whats more important

airport wise scl is a better place to transit than eze

Seat wise I would probably go with Qantas as currently their sky bed seats would be better than the Lan's old offering, however Lan are in the process of upgrading their a340 to new lie flat seats which is better than the 170 degrees or so on qantas, but I am not sure about the progress on this as the website makes no mention of whether this has started, but all of the 767's are supposed to have been upgraded.

So best bet stick with qantas, also qantas flight from eze is direct no stops whilst Lan stops in akl on the way to sydney, so it depends if you mind stopping or prefer the direct flight.

Service wise I guess its up to personal opinions but I would say qantas service in J is more consistent than Lan

I am sure others can provide other information if I have missed anything

regards