I have never used room treatments. I have huge a couple of area rugs on a wall or two to eliminate the " clap " affect. With speaker that doesn't double in the bass you should be fine. Those Chapman's use a transmission line which really makes for an accurate and deep bass and should not be a problem.
I am guessing the Spendor would be good and the ProAc.
I am guessing the Spendor would be good and the ProAc.