I know I seen the mag rankings, but are the USA mags horrible, or are they worth about 15 bucks?

In my experience, they are horrible or very poor. Not worth $15, more like -$5. In other words you would have to pay most folks to take them off your hands. Some people have some that actually work fine though, go figure. On the plus side you could use them for practice in clearing jams in your rifle.

Yes they are the worst, and for $15 can you buy used USGI mags. I don't think 5 USA mags would be worth $15.

Most if not all of the USA mags are just about worthless.  I remember a couple of posts that validated this.  A former employee of USA stated that the tooling USA used was worn out but they continued to mfg mags that were out of spec.  Second, a AR15 member examined all the parts taking measurements and compaired the USA AR15 mag agaist a USGI AR15 mag.  The USA mag was totally out of spec and the materials were sub standard according to his report.  My personal experience with a USA mag was that it would not even fit in the mag well of my AR.  I sold it for $1 and felt I overpriced it and it cost me more ($4.50) to ship the peice of junk to the buyer.  It was worth the money to get rid of it.

Absolute GARBAGE.

fifteen bucks? Sure, if that's what you're being paid to take em.

Meplat-

If you you sold it at a loss why not just save some money and taket it to the range and blast it. That would be more fun any way.[;)]  

Here we go again.

I bought 10 of these way back when (when I didn't know better).  I offered them for free on this site and I paid for the shipping.  Two people took me up on the offer and I split it between them.  They were going to use them for a special project blah blah blah.  It actually was a very cathartic experience.  They simply don't work.  You can't switch out the 'internals'.  They most often don't even fit into the mag well.  It is a fraud, pure and simple.  For God's sake, resist the temptation to buy one and buy USGI or the recent British SA80 mags.  I can assure you that the aggravation you will suffer with the USA mags is not worth it, even if you got them for free.