From counting pew rows in the picture, I'm guessing it's about 30 - 35 feet deep. If that's the case, in my opinion the SX-80 size speakers will not throw far enough, you'll lose your high end due to the inverse square law. You would have to put in a second row of them further down the room. Which is good if you can afford the number of speakers but I would recommend you get a DSP so you can tune them and time align the system if you use a delay system. So a bigger speaker that will do the job may be simpler option.
Also you might check out JBL control series speakers like the Control 29's or 30's if you choose speakers this size.
Rob