I prefer a leather pancake style when going to court. They hold the gun tight and minimal support is needed from my belt. I dont have a G30, but do carry a P220 or G23 in a suit. The serpa is popular with the guys I work with, but I like both of these;
http://www.safariland.com/product.aspx?pid=0701
http://www.safariland.com/product.aspx?pid=527
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