Keep in mind that the MPEG4 is the format use to tramsmit the signal to the reciver, the reciver must then decode it to analog NTSC.
The DVD recorders use the analog outputs of the direct TV recivers so this will NOT change. Here is another Sony you might want to look at. John
http://www.sonystyle.com/is-bin/INTERSHOP.enfinity/eCS/Store/en/-/USD/SY_DisplayProductInformation-Start?ProductSKU=VRDVC20&Dept=computers&CategoryName=cpu_Sony_PCAccessories_CD%2fDVDBurn_DVDirect
alot of concern has been looming about direct tv's change to mpeg 4 format and incompatibilities with tivo's and direct tv recievers. What about dvd recorders? I bought a direct tv tivo unit 1 year ago and they (direct tv) said that they would upgrade the reciever if needed, but what about dvd recorders. I am interested in the panasonic es10 and the Sony GX300 and am holding out till I can find out if they will still work in 6 months with Direct TV. Also any pro's / Cons on these units or suggestions on another model/brand would be helpful.

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