current draw from satellite radio

I'm doing the 12v front power outlet mod on my 06 to have unswitched power available for my Sirius S50 (has the ability to record up to 50 hours...like a tivo). My question is do I have to worry about a power drain or is it such a negligible amount if left on overnight. Does the 12v plug draw from the traditional battery or the hybrid ones? What happens in a similar scenario like when a dome light is left on for hours?

 

<div class='quotetop'>QUOTE(redfxrs @ Feb 5 2007, 10:44 AM) [snapback]385538[/snapback]</div>

power outlet mod is now done (thanks coastal dave). the Sirius S50 shuts down by itself 30 minutes afer the last recorded song, so unless I program more recordings, i don't beleive the power draw will be a problem. Still, I was hoping to get some technical expertise concerning the source of the 12 volt power (drawn from which battery) in this forum.
I'll re-thread in audio and electronics to see if i can get a hit there