[CCIP]

I think TMO gives you a little more variety - just as Ducimius' goal with it, really, to be realistic but not overbearingly so. RSRD, meanwhile, is the most thoroughly researched piece of campaign work I've seen in any game. I actually don't find it terribly hard to find shipping, but you really need to be patient and know where to look for it. However if it's convoys you want, you'll get them and you can sure savage them.

So my own choice is RSRDC, actually. I think it takes a little bit of a bite out of TMO's initial difficulty (in some areas though not others) and variety, but for me the level of accuracy in the traffic is too hard to pass up.