I've had great flights on Iberia (within Europe), American West and Olympic. As for KLM, they have probably declined the most of any major airline. The reason we are so upset at KLM is that they used to be a pretty good airline. However if you fly them with no expectations they aren't too bad. I've only flown KLM twice this year though.

OTOH, United in some ways has declined far more than KLM. UA is still a good airline in some ways, but if you based them on what you expected in 1998 for instance, you would be highly dissapointed today.

LCC's aren't quite mainline, are they? I simply won't fly them except for the few times I've had no choice but to fly Southwest. Ugh!