I'm on the same situation again, I have tested SH3 and SH4 and now can't decide whether to start campaign on SH3 or SH4 as Atlantic is still only real place to sink ships. You will surely enjoy SH3, t's at least for me visually enough, it just for some odd reason seems to work slower than SH4 + OM.. Gameplay seems to be about even but then there's really many great mods for SH3.. It's so hard to decide!
Welcome to the forums even if it's a bit lately said
I've noticed that's great place.