I was wondering this as of two days ago and ended up running across this…
https://dvxuser.com/V6/showthread.php?t=133576
it actually shows quite a large difference between the hvx200 and hvx200a. It is what made my mind up that the hvx200a was definitely worth the money. If the video doesn’t work for you, just follow the link in the first post to download the codecs.