- They are latching connectors
- They have better contacts (much better) than jacks for high current
- They can't accidentally be mismated with jacks!
- no exposed conductors on an umplugged cable. Wuould you want to short out your 200W amp by dropping the end of a jack lead onto a metal surface like a speaker stand leg?)
- There are 4-connector and 8-connector versions with standardized pin assignments for biamping, stereo and balanced drive (both pins live + and - instead of hot and ground) (you probably don't need this though)
- they have screw terminals for reliable and easy assembly
- they are more robust
- any PA speaker you buy with jacks has been designed down to a price, not up to a standard.

Jacks are ok for a 100W foldback rig (I use them for that in my band), but if you're talking about 2kW of amplification and bass bins you're definitely looking amateurish with jacks for your speakers.

Anahata