Question regarding D2's battery life/transfer speed and SD card

[REM333]

I plan to buy a 4GB D2 for about $200 and a 4GB SD card for about $40 making the total space 8GB for my future player. My main concern is, what will happen to the battery life and the transfer speed to the player if I use the SD card to play from videos, music, etc... (I know that the transfer speed to the player without the SD card is 5MB/sec, correct me if I am wrong)?

Someone on the comments section implied that the battery life would actually be halved (not verified claim).

[CrowdAds]

[AirTimid]

I believe running off the SD uses the battery twice as fast. So, essentially 20+hrs for audio and 5+hours for video, which is about the norm for other players.

[REM333]

Thanks a lot for the quick reply!

Anyway, does that mean that it will use the battery much more quickly simply if the SD is plugged in or if the player is accessing the data from the card?

[dfkt]

I cannot verify if this is true or false - but I have the feeling draining the battery twice as fast by using the SD card seems a bit exaggerated. However, I have to test it with a stop watch. No easy task with a battery that lasts as long as the D2's.

[AirTimid]

That was just a conservative guess from what i've read on various boards. I think the SD only uses power when it's accessed, so, just having it in there shouldn't affect things too much.