which is medal?
You mean "metal" with a "t". The one with a "d" is the kind you get when you win something (i.e. an Olympic medal).
Going back to the topic, the general rule of thumb is that the KWA will be better built and will last longer. If you have the money for the KWA, get it. You will not be disappointed.
Google and other websites are your friend:
http://www.airsoftgi.com/product_info.p ... ts_id=5718
According to one of the reviewers, it is all metal.
I notice that you have the KWA KP45 on your list if replicas in your profile. If you like the quality of that weapon, then you'll probably like their version of the M11A1.