The Panasonic 8K has not been reduced to 2400. All authorized retailers can only go down at low as 2600 right now. Just give them a call and ask if you don't believe me.
Sure, you can get the Panasonic 8K for $2400 from smaller non-authorized retailers but then you only get a 2 year warranty, and no 3D glasses.
The Epson 5020 is $2600 but that includes a 3 year warranty and 2 pairs of 3D glasses.
The best deal you can get for the Panasonic 8K is from a place like projectorpeople for $2600. But then you send in the UPC to Panasonic and get $100 back as well as an upgraded 3 years warranty and 2 pairs of 3d glasses. So it's really just $100 cheaper than the Epson.
Brighter in dynamic (good for 3d)
Better black levels
Better warranty (if you use more than 1000hr/yr)
Screen Door Effect
High input lag (bad for gaming)
Low input lag
Worse blacks levels than Epson
Worse warranty (if you use more than 1000hr/yr)
That's how I see it at least.