I'm in the same boat as you, 88" ceiling and I have only 6" from the ceiling to the white screen line.
At the moment I still have a 2050A, but looking seriously at this pj.
My setup is in the garage, so I can do whatever I want. I ended up using a pj lift(cheap on Ebay). The pj just pokes out from the ceiling, just a bit.
I also have a center speaker issue, I don't want it under the screen, since it is a garage. Not using for parking, but still, once in awhile I need to work on cars.
I have decided to build it into the ceiling/attic, in an angle. I have Klipsch RP-450C.
Initial plan it was to motorize it, and I actually made all the hardware, but I have decided against it, because of the limited "ceiling space".
It seems like, the 5550 would be a better choice.
Living Room: Samsung UN65JS8500,Onkyo TX-NR676,Klipsch R-28F,Klipsch RC-62II,Klipsch R-14S,Polk Audio 80 FX/RT(Atmos)
Bedroom: Samsung UN55MU6290,Onkyo TX-RZ610,Onkyo & Fluance speakers
Garage: Epson 5040UB,Elite Screens 125" motorized screen,2xKlipsch RP-160M,4xKlipsch RP-150M,Klipsch RP-450C ,2xKlipsch CDT-3800CII/2xCDT3650CII,Klipsch R115SW/R110SW