Welcome to the Pacific! After SH3 I never thought an AMERICAN sub experience could compare. How wrong I was! After playing SH4 I've been inspired to read a ton about the submarine effort in the Pacific, and there's just as much, if not more, to sink your teeth into when compared to U-boats in the Atlantic. Enjoy the experience, and yes...you'll LOVE the radar!
Good Hunting,
Howler
p.s. I do miss them screaming, "Aaallllaaarrrrmmmm!" dearly though...oh well...