gear advice please..

hey all
So as i posted a short while ago . i stated that im about to make an order to warbonnet pretty soon and am gatherimg my shopping list.. with that said,ive also been shopping for a new sleep bag. a 3 season is what im thinking as i do hang in cooler/colder weather ,and ofcourse summer..my question is about the bag type.. i have decided a down bag is the way to go with weight savings and compressability. a top quit was considered but i think a yeti might be a better way to go for me .. So ive been thinking that with the yeti uq (havent decided what version yet) would it be safe to say that i could go with a lighter bag or one that has higher temp rating like a 30 deg? reason why i ask is 1 cost.. and 2 weight .. or would it be better to gear for the cold and pack whats needed for that trip? ive found picking out a bag is not very easy.. as i do hang most of the year.exp dead of winter.but ive been known to do that aswell.but those times are wild hair or just cabin fever..
doesnt happen very often..
Ive been reading reviews on sleep bags.. heres one ive been really considering..
http://www.rei.com/product/762518
or could i go even lighter? considering the uq added?
thanks all really need adive here as ive nevr bought a down bag..

In as much as I use a sleeping opened up like a quilt... I would say go with a quilt. I do like to be able to wrap the extra sleeping bag around me when it is cold but then it is a synth bag and I am pushing its envelope.