Theres an outdoor shop with a used gear section near me, the gear is color coded and each month the previous months shit that hasn't sold gets discounted, so the longer it sits the more of a discount you get (OGE Burlington,VT)

I was in the Army so I had some misc gear I have been using without having to buy much, and I know some basic stuff, but we never really did actual backpacking like I wanna do now (artillery retard)
Ive been doing some light 1-2 night backpacking in the mountains where it gets to the 40-50s at night right now sometimes and would like to continue for a few more months at least

Right now im using a Kelty Callisto 30 just cuz its what I had around the house and I didnt wanna run out and buy a buncha new stuff

Its 4 lbs which isnt really a problem, but its just so big it takes up like 1/2 of my pack, more space than my tent
I found a mountain hardwear Lamina 30 for 60$ that comes with a compression sack, and when I packed it up just to see it def felt lighter and more importantly its like 1/3 of the packed size as my current bag

It looks to be in good shape other than some faded colors and a missing pull string on the zipper

I was gonna buy it, but does the filling get destroyed if it was stored compressed?
Is there a way to tell the condition of the fill material?

pic related, me chilling after illegally camping in the alpine zone on Mt mansfield last weekend, shit was so cash