SureSh0tI was looking into these clock chips just to get an idea what the difference would be, and it looks like you have to decide whether a tiny bit over one-tenth of one trillionth of a second worth of jitter (the difference between 200fs and 82fs, according to the chip manufacturers) is worth $54 to you. Of course, I'm replying to an old post where this was an option... for this run only the advanced version is offered.