The LG's motion blur reduction feature is really backlight strobing. It improves picture clarity, reducing perceived blur and ghosting, et al.. It does not affect response time.
As James mentioned above, a better measurement in terms of your gaming experience would be input lag. Both the LG 24GM79G-B and BenQ XL2411Z are measured at 10ms. Anything below 20ms is considered "excellent", by industry standards. Professional gamers would say 15ms or below.