You said “front row” which implies you are planning more than one row of seats. In that case you may benefit more from QS speakers in the back if your back row of seats will be closer to the wall. I haven’t experimented with back speakers and multiple rows of seats but my feeling is that QS speakers might sound better. Be interesting to hear from anyone who has experimented with direct radiating and multi-polar speakers with multiple rows of seating.
I’m fine with using one EP500 in my room which also has an adjoining kitchen/dinning area of almost equal sized. Makes more than enough base for me. At some point I might consider a second subwoofer mostly to even out the bass I cant get it where I like with placement and room treatments. Also a second EP500 cost a lot less than a second EP600/800. The EP500 even shakes my seating if I want it to but for the ground shaking bass I prefer the Buttkicker especially now that I have dual configurable subwoofer outputs on my receiver. IMO the Buttkicker’s shaking/rumbling feels much more real than that induced by a subwoofer.