I just tried, and the software player does seem to do a better job than the web player. It certainly sounds different. I don't have much trouble following Ng at 150% on the web player either, however, so it's hard for me to make a useful comparison.

I should say, though, that the machine learning videos don't seem to be loading fast enough on my connection for smooth sped-up streaming using the software. This makes the software pretty useless unless you pre-load the videos or are willing to put up with the frustration of intermittent buffering. I don't have this problem with the AI videos (or youtube videos in general).