I am a screen printer in real life. It is what I know, it is what I do. I see so many people on eBay getting ripped off because some kid at home is printing iron ons and selling them as something else. Basically there are a few levels of quality clothing.
Low Quality: Iron on - Made at home, peels off and discolors within 1-2 washes.
Medium Quality: Heat transfer - Printed on a high DPI printer, applied with a commercial heat press at or above 500 degrees F. Lasts years, fades slightly.
High Quality: Screenprint - Printed on a press, color by color, with plastisol based ink. Lasts years, doesn't fade, cracks over time.
Designer Quality: Fabric - Fabric is either sewn to make a piece, or applied to clothing. Lasts years, expensive due to quality and production time.
If you want to be disappointed, go with the Iron on. You will be kicking yourself in the butt shortly after getting your item. You can tell if you have an iron on if the edges of the image appear to be different than the image APPLIED to the shirt. Usually people applying such low quality prints don't take the time to properly trim the extra around the edges. This will look like white or clear usually.
If you get a heat transfer you'll be in better shape. Though not the quality of an actual screenprint, heat transfers(if applied commercially, not just saying they did) will actually form a gas when its being applied. This gas seals the transfer to the fibers of the shirt making a much better, longer lasting image.
Screenprint is the way you want to go. They last a very long time.
*****HINTS THAT ITS AN IRON ON*****
The auction states its only available in WHITE. If it was commercial, it would definately be available in more than one color...
The auctioneer states any size is available. If they have a lot of sizes, they really mean they have none. They want you to buy your item, then specify the size, so they can go out and get the blank shirt, to go home and print an iron on out and start ironing...something you could accomplish yourself at your own home.
Feedback says something like "OK" "Not what I was expecting" "ok quality" etc... Thats a buyers way of saying "This item sucks, but I'll not say it so the seller won't retaliate and leave me negative feedback."
Hope this helps all of you!
BTW anyone who looks at my auctions will see nothing less than a heat transfer. ;)