I'm planning on going on a 3 day trip in the mountains of Southern NM at the end of Jan. We're expecting lows to be no lower then 0* and thats a big if with this years warm winter in our region. Anyhow I have a cheap down bag that's kept me warm to about 30* to upper 20's but I was thinking of replacing it with a golite 3 season quilt, which are on sale atm. Well the quilt is supposed to be good to 20* and supposed to be more accurate this year then last years model. So if I take my bag and quilt I was thinking I should have plenty of loft above me right?

Is there any reason why this setup wouldn't work?

Since winter lasts about 2 months down here I cant really justify a nice down 0* bag and dont want to buy a less expensive synthetic bag but if for any reason its a better option then layering Ill go that route.

Thanks for your help.