Gas log fireplace

[wjcalderon]

Yesterday, I had vent-free gas logs (natural gas) installed in my existing fireplace.
I did this primarily for backup heat in case of power outages.
Yesterday was pretty cold for the Deep South and I'll have to admit, it felt pretty good to sit there in front of the fire.
Does anyone know how efficient these things are?
On the days that I spend most of my time in that room, if I turned my central heat (also natural gas) down really low and just used the fireplace, what effect might that have on my utility bill?
Also, should I leave the pilot light on all winter or re-light it when I want to use the fireplace.
For some reason, leaving that "little fire" burning all the time scares me a little.
Any advice, input, suggestions are welcomed.
Thanks....

[2ndGenGranola]

We leave the pilot light on year round. It uses minimal gas. I find our gas log fireplace will heat up the house much faster than the central unit. We then turn off the fireplace and it will still radiate for a period of time.

When it is very cold and you first turn it on, it is going to burn and pull much less efficiently. After about 5 minutes, it will be "up to speed". You may even want to crack a window or turn on a ceiling fan during that period.