I do believe in the research of Toole/Olive/Harmon International that basically says -- with all other things being equal (acoustics, placement, volume, etc.), the speakers with the best true off-axis (polar response) and on-axis frequency response will sound the best to most people.
Yes, all the speakers I buy, including the P362 & P163, have very good 60 degrees horizontal off-axis polar response and on-axis response.
But that Pioneer is +4.5dB. That is not a very good response. The definition of a good response is less than or equal to +/- 3dB (same as your name

), not +/- 4.5dB.