I have not heard any of the newer Def Tech.
The BP-8080 measured pretty well:
The BP-8080ST’s listening-window response (a five-point average of axial and +/–15-degree horizontal and vertical responses) measures +3.12/–2.11 decibels from 200 hertz to 10 kilohertz. The –3-dB point is at 35 Hz, and the –6-dB point is at 33 Hz. Impedance reaches a minimum of 4.58 ohms at 273 Hz and a phase angle of –34.63 degrees at 179 Hz.
http://www.hometheater.com/content/definitive-technology-bp-8080st-speaker-system-ht-labs-measures
So I think the BP8020 would also measure well, except with less bass than the BP8080.
Don't listen to SOME of those sales people. They will tell you anything to sell. Some sales people are more honest and knowledgeable than others.

Just set you Center to SMALL on the receiver.