Your question is bit confusing. The '2x dvdr
dvd-r Sony DRU-500a' is not a media description. Since you have the 105,if I'm not mistaken,you can upgrade the firmware to burn DVD's at 4x (half the time of 2x),by going to the Pioneer website,or
a number of websites that have that firmware upgrade. Do a search on Yahoo for 'Pioneer
105 firmware upgrade',and after you the upgrade,search out some 4x media,I recommend Memorex,but you may find a different favorite. From my searches,Pioneer media is too expensive,read what members have to say here,and that should help you make your decision....