They're both good mods on their own right. In my opinion GWX is better but that's just me talking. My suggestion is to install both of them and see which one is better for your type of playing. If you need to know how to do multiple installations check out this
http://www.subsim.com/radioroom/show...22&postcount=3 and this
http://www.subsim.com/radioroom/show...28&postcount=2