tex - most of the exhausts are exactly as you describe - they dont split again at all. The Y pipe branches together, goes to a single midpipe and a single muffler that has one inlet but dual outlets (tips). It is still a single entry muffler which is all that matters

The GReddy evo 2 is also an excellent unit - great welds too. It comes down to what you like the looks/sound of

 

But it makes for gigantic mufflers. Have you picked up the stock muffler? Can't believe how much that thing weight!

I don't know, a single canister single outlet exhaust seems more logical to me at that point. That is what I meant.