BTW, the Verbatim 8x media (which is MCC003) will burn great @ 12x on the 1620 with the right firmware. I am not sure which firmware the 12x capability started but I know B7P9 and B7S9 both support it.
And, I just received/tested my 16x media. A 12x burn only takes ~10 secs longer than a 16x burn so I wouldn't bother spending the extra money for the 16x media.
Here is a link to the 8x media but I wouldn't buy it at that price. The link is only supplied as a reference so you can get the part/model number. I bought the same 50 pack spindle at BestBuy for $20 a couple weeks ago.