I would say for anny shot the Meteor is really good. The Z plastic on the comet tends to come out of it's anny flight a little more. Honestly the X Comet is the best plastic for comets. It hold every line perfectly with far less effort. Allows a lot of touch to be put on your shots. Either way you can't go wrong here. The Z Comet is a great disc too. If you have to choose between the Z Comet and the ESP Meteor I would say try the meteor out.
IMO the Z Comet but I don't feel that my meteor is beat in enough to perform the shots it is designed for.
The Z comet is an excellent tailwind disc that will go very straight, will have good distance and requires little effort, when beat in is also is great for those long annys that you would like to land flat and not roll.
I have a new meteor (stable) but have thrown a seasoned meteor, these discs are great at 250-300 shots that you need to go straight but have a slight right fade, I have not extensively used it as an anny disc to give any feedback.
X Comet is $$$$, Just playing catch with one the other day made me get a half chub : )
Comet is one of the greatest discs ever made. Learning to throw and mastering this disc will make you famous.
Meteor seems a little faster to me than the Comet, so I'd use the Comet for shorter and Meteor for longer annies. Then again, a max weight Z-Comet is a pretty long disc as well for longer annies. I think the discs are close enough that you should just pick which feels the best and learn throw it the way you need it.