imho the "P4" means Seoul led here ...
... because it needs 1 sec for ppl with no knowledge at all, to learn that - when its is BINs that are meant - P4 is less bright than Q3 is less bright than Q5 is less bright than R2...
Then there is much more than the bin (that is stated with the lights specs).
The more rugged light from a respected maker with a P4 bin will give You more, than the immediately failing R2-bin Ebay offer
XR-E to P4 is a subjective matter.
I would take
any XR-E Q bin over the most recent Seoul bin at any time
(not really helps You, or ?)