LWAMI is for those that want more realism in the stock sim, it modifies the sonar and sound profiles to make it more realistic to real life, but to the best of my knowledge you don't get any graphics upgrades or new playable platforms like you do in RA. Also LWAMI is not comparable with RA so you can't run both. This is what I've heard but I haven't tried LWAMI, I love RA too much to switch.
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Americans make better submarines? No my friend, Russia makes better submarines, Americans just make better computers
