use or not a board to capture video

extending this discussion I have an issue. I have a board for TV turner which I am not currently using which allow me to capture video in JPEG-2 format. It is a pixelview play Tv pro ultra or an playtv jpeg2, doesnt matter I have both.
However I also have a dazzle device, which I am using and which allow me to connect my VCR and capture the video using my Pinacle software.

My issue is, is there any advantage for me to use the pixelview board? is there any advantage to have this hadware to capture de video? Is there any benefit in performance against I use this board versus my desktop CPU?