New Korean M1 Carbine mags?

I've read some good things about these new 15 and 30 round mags being imported from Korea. Anyone seen them and have an opinion?

I have bought one of each to try them out. They both work quite well in my carbines. The metal on both is thicker than other after-market mags. I was surprised that the 30rd did great and didnt jam or misfeed. I still prefer the USGI 15's and will continue to buy them from CMP. But I am considering buying a few of these Korean 15rd and 30rds just to use at the range. That way the USGI's don't get the banged up abuse of range duty. I think the 30rd mag is a great buy - if you can afford the ammunition to fill it up and shoot it a few times!!!