Brian, I'll leave the coverage questions you have to the real professionals, however I'll give you my subjective experience using PK gear. I manage a modest sized (340 capacity) club where we have an installed JBL SRX system. We do small weekly DJ shows on the JBL system and full out monthly touring DJ shows using a brought in PK system. We have used both the CX line and the Klarity line for our monthly shows.
As far as the top boxes are concerned, I prefer the sound of the JBL SRX's over both of PK's offering (cx and klarity). There seemed to be a lack of mids in the PK boxes. This observation seems to be consistent with reviews of other PK systems on tour. To be fair, the house system has had more tuning done to it as the PK system is usually tweaked on the fly by DJ's and promoters throughout the night. Although PK's CX line is very well made, the lack of pole mounts drove me crazy. As PK usually custom makes cabinets to order, I'm sure they could configure the boxes to your needs.
Now on to the bass. There is no contest here. PK CX-800's are the real deal designed for EDM promoters by EDM promoters. Never have I heard anything so deep and powerful and effortless in a compact pa system. We run about 127 dB @ 50hz center of dancefloor and my kidneys shutter on every hit, yet clean enough to hold a conversation with someone next to you. When I look at our SRX 728's I now see tinkertoys. The SRX's are great boxes but they can't keep up at ~30hz like the CX's can. FWIW we measured the PK Klarity subs 2 dB louder than the CX's at 50hz, although at 30hz the CX's win out, that 19mm x-max is meant for EDM music.
Now on to the business side of our shows. With the amount of crap systems out there and promoters not knowing the sound side of things, having the PK brand on your event that EDM enthusiasts recognize sells tickets. People will drive in from out of town to hear a PK system because "Bassnector, Skrillex, etc" uses it. It is such a draw in the EDM scene in Canada that PK has to protect their logo from unscrupulous promoters using their logo on their posters without owning any of their gear. Even if you find and use better gear and achieve better sound, consider the types of shows you do and whether or not gear snobbery of your intended paying customer is at play.