Hi I Thinking of buying the Sony RDR-HXD870 but was wondering what was the best blank media to use with it as the manual I have read online is not very clear

Thanks in advance

It looks like dubbing a recording from the hardrive to dvd while watching the hardrive recording results in lower picture and sound quality than while not watching the recording.
I have not done repeated tests, but this seems to be correct.
The instruction book tells you how to dub without watching the recording at the same time as well as how.

I have also just tried a Maxell DVD+RW and a Maxell DVD-RW.
Both have only been used once before.

The DVD+RW is rated at 4 speed maximum and the DVD-RW at 2 speed maximum.
The Sony burns them at their maximum speeds when high speed dubbing is allowed.

I thought the DVD-RW would give a better picture and sound since its being burnt at half the speed.
But it was the opposite, the DVD+RW gave much better picture and sound.

The manual warns you that if you burn DVD+R or DVD+RW that it will be recorded in 4:3 aspect ratio.
This is wrong, if you dub from the hardrive to a DVD+R or DVD+RW the aspect ratio is perfect.

I did however have the 4:3 problem when recording straight to DVD+RW (not sure about DVD+R) without using the hardrive. It does not record a 16:9 Freeview program in 4:3, it simply records the program but sets the wrong aspect ratio flag, so all you have to do is tell your TV to manually switch to 16:9 (wide) mode for perfect 16:9 playback.

Maxell DVD+RW are cheap at the moment, I got a 25 cake box (on a spindle) for £11.23 from Asda, www.play.com are selling them for £9.99 including delivery.
Maxell have a reputation for being a quality manufacturer and are not the very best, but are close in quality and reliability to the very best.