Solid Core Wood Doors or Steel Polyurethane Core Doors?

I have a quick question.....or maybe questions I have the opportunity to buy some NEW Steel Doors in Jamb (polyurethane core), and painted the color i already need them painted (RED) by a contractor pal who has an overstock in his warehouse. I also have some solid core wood doors, not in jamb of course, from an elementary school demolition....they are about 1 3/8" thick. How much of an 'isolation' or 'STC' difference would there be in these doors if i were to use 2 in a wall? that wall really being two walls and an air gap between rooms/booths, yes 2-leaf, and yes with the proper seals. Im sure the solid core wood door would outperform the steel door, but i guess i just need to know by how much? A little or A lot? It would be nice not to have to build door jambs between rooms, as i have 4 separate rooms/booths and that would mean building 8 door jambs......i guess i also forgot to mention that im doing 90% of the construction alone. :( And just so you know how enticing the door 'deal' is from my contractor friend....he'll sell me 8 doors for $70/door....these usually retail for $299usd. so the price is VERY ATTRACTIVE as well as the ease of installation. here's to hoping....thanks for your time moderators!

In doing a bit more Google digging it seems like polyurethane core doors have a pretty good STC, but the information is very vague and sometimes product specific. The brand of door above is made by MASTERCRAFT here in the states, all i can find on their website is an efficiency rating. anyone care to chime in?

" so the price is VERY ATTRACTIVE as well as the ease of installation." This is usually a comment reserved to the home owner:) If the price is attractive, meaning low, and the installation is easy then you are most likely looking at the wrong product...or looking thru the wrong set of eyes. A solid core wooden door is going to provide a higher transmission loss. Forget sound transmission loss since this only concerns the listener with the frequencies that the human ear can detect. A good STC can result in a poor TL in the acoustic arena, and we concern ourselves with low frequency which the TL takes into account. All things being equal, jambs, seals, pull handles and the like, the solid core wooden door is going to out perform the metal door.

Thanks xspace I was beginning to wonder to myself as i dug through the archives of google 'Just build the damn frames/jambs and know for sure' thanks again for the reply.....this thread hopefully will get cached in googles search engines and others like myself will be thwarted.