" thought i read a story about a new laser head(?) that would go past the 16x speed limit on dvd burning"
yeah but what is the media limit? DVD media that can burn at 20x would probably be very hard to manufacture in large quantities and cost quite a bit. Same reason the CD writers never went above 52X. They had the ability to do 56x but no media maker had plans for media past 52x or so I recall.