Brent -
Some of those bags might be a little older perhaps hanging around at the factory or Campmor may have bought out the entire line. FWIW, they don't seem like bad deals - Good entry level bags, considering the fills were top of the line synths 15 -20 years ago.
I have 3 slumberjack down bags (good ol' pro-deals) that are at least 12-13 years old and they are still in fine shape.
I did have a SJ lite-loft bag about 15 years ago and returned it after 2 years due to loss of loft. At the time, the SJ rep said that they were replacing a lot of these bags as the material lost much loft within a year or two.
I had posted bits of the following over at ADK forum over the summer - It might help here. There's a lot here and it might be overkill, but if someone else beneifts, then great.
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Here's a quick rundown of fill materials. I am going from memory, so if anybody has additional or more refined info, please add or correct.
FWIW,
Dupont Hollofil 808 is the forerunner of Hollofil II and is an ancient (in terms of camping gear) single hollow core fiber - Think of a very small tube -Traps air inside - The more you can trap air, the better the insulation - The hollow core allowed it to loft a little better than standard solid core fibers that were even bulkier and heavier. I think Hollofil 808 came of age in the late 60's or early 70's.
Newer than 808 is Hollofil II - This is a 4 hole fiber (think of a tube with 4 holes or chambers that extend from end to end.) This offered more trapped air in each strand and even better lofting. This was around the late 70's IIRC.
Next was Qualofil - in the early/mid 80's. This took Hollofil one step further as it was a strand with 7 holes running from end to end. More trapped air, lighter material and better lofting.
Around this time (early 80's IIRC) Hoechst of Germany (My old predecessor company) came out with Polarguard (later 3-D, then Delta) which was a competitor of Dupont.
Dupont's next step in the early 90's was Microloft which was a fine polyester fiber (thinner than human hair strands) that was lighter and supposedly would loft better. Around the same time - 3M entered the picture with Thinsulate Lite-Loft - I beleive this had around the same track record as Dupont's Microloft.
I beleive Dupont then developed Thermax - But I don't know if or how it performs in sleeping bags.
The big problem with these bags - Especially the older generation fills - They are to heavy to be effective or efficient for long. Like a classic aerodynamics fuel/efficiency struggle - (The farther you fly, the more fuel you need, the more fuel you need causing a heavier plane requiring even more fuel.....)
With these lower end insluations The more insulation, the more loft you should get in theory, but in practice, because the fill is so heavy, you lose some loft... At some point you cannot just keep adding fill material without collapsing all loft
Also, the loft will likely go flat or get flatter (if not already) within a short period of time - Meaning that perhaps next year your 20d bag might be a 30d bag and in 2 years a 35 bag. 4.5 lbs is a lot of weight to carry.for that bag.
Finally, keep in mind that the hollofil series DO NOT STUFF well at all. It might take your whole backpack to fit this thing in - How small can you get it when it is 20d out and you are cold and trying to pack up....?
There's also construction and bag material, zippers and such - way too much to get into, but FWIW, these seem like great entry level bags, car camping or boy scout bags.
