Sorry for the long delay!
Unfortunately it looks like this site is doing some things to trick us! I tried it from here, the original downloaded video (before conversion) is also tiny and low quality. We would need to have some custom check to look for the best quality video as right now it is just finding the smallest one. We may be able to add this in the future.
In the meantime you may need to try a screen capture application such as Jaksta Screen Recorder for this site. Sorry I can't be of more help here.
I recently captured a video from the following url: http://northpoint.org/messages/what-makes-you-happy/peace-with-god/
when comparing video using browser to play vs using converted video (.MOV), it has very poor quality. Any answers?