To me, you need to be more specific with your interpretation of "throttle response" at low rpms......
Some have had or are having problems with "lag" and the (fly by wire) throttle mechanism. This could be someones view of poor throttle response. The gearing in the newer models is not as low as in the past. As a result, low speed and rpms are not as responsive......Cam choice plays a part in where you will really get good response, rpm range-wise.
Is your set-up "stock" and you are trying to max out your torque numbers on the low-end.........Mine doesn't come on good till around 2500 rpms or so........but I went to a T-Man 625 cam and other stuff.
I'm not trying to confuse the question you are asking, just thinking you will get better answers if you relate a little more about what you are after.