I realize that this is an old thread, but someone might still find it relevant. I bought my PING G 15's in October of 2010. When I told the salesman at a national chain golf store that I wanted a set of the G 15's and the reason why he tells me that they are all made in China. Well, he was partially correct - as it turned out the irons that I got that day were both made and assembled here in America. The box that they were packed in had an American flag on it as did the shaft of my 4 iron. Also, the origin of manufacture sticker on the shaft indicated that the heads and shafts of that set were USA made as well. Now my driver, fairway wood, hybrid and putter that were also bought that day are definitely made overseas.
Fast forward to March of this year - I mail-ordered two G 15 Lob wedges from that same chain. When the clubs arrived I found that one was made in China and the other was made in the USA as stated by the origin of manufacture stickers on the shafts. This confirmed what I was told by PING back in 2010, 'most iron production is done in China, but the Arizona foundry is put to use when there is a backlog of orders (particularly when a new model is introduced) and the Chinese facility can't handle the demand.'
Bottom line, call PING and ask which model clubs are USA made and which aren't.
