The firmware page have posted a flashing guide/faq for the two new unofficial v1.30 (RPC1 and with improved media support) firmware...
Just a sample of the FAQ
Q:This hacked firmware stuff, what is that about?
A:Well, as you might have noticed, burning-speed to a DVD-r media is limited by the drive. Because of this, you can only write at higher speeds to certain media, if this media is certified by Pioneer. Because some media which aren't certified by Pioneer, allow faster burning then 1x (for example : in a different DVD-Recorder), we also should be able to burn them faster.
Click at the 'Source' link to visit the whole FAQ!