My Friend DVDRW Test Result and Need Your suggestions

This Is My Friend DVD-RW Nec And I Do Test For DVD+R Aopen (Prodisc) And Ridata(Ricoh) With Different Speed

But I Can’t Show 8x In Settings List So I Choose 4x And 7x , 10x

What Your suggestions For This DVD-RW And DVD Blank Quailty (Should Be Buy After That) ?

Which recommended Speed Should Be Burn After That ?

Your suggestions Return This DVDRW And Order 7170a , Lite-on 20a1p Or keep IT