I have a G17 in a Sig229 Crossbreed IWB holster right now, canted about 30 degrees frontwards and am wearing a longer than usual, and less tightly fitting t-shirt that hides it just fine.
I really don't like the walther mag releases, maybe I haven't shot enough with them to get used to it, but I've got big enough hands/fingers that the standard mag release is not a problem for me...