Wayne Parham Messages: 18758 Registered: January 2001
Illuminati (33rd Degree)
I'd say they're both equally competent. Both have similar characteristics, tonal balance, directivity, etc. The four π speaker is slightly more efficient because of the larger midwoofer.
Really, you should make your choice based on the midwoofer family you prefer. If you want AE, go with the three π. If you want JBL, go with the four π instead. Of if you plan on using the Eminence drivers, the four π has the cast-frame Omega 15, whereas the three π has the stamped frame Delta 12LF.