Thunderheader aint bad either Cheese - and yes, the two into ones do have a sound all their own. Often wondered why the factory put the over and under pipes up there. Is your bike injected? If so, may need a re-map to get it right on with the big pipe - don't know for sure, but my buddy who has the bike shop put a Power Commander on his Ultra Glide along with the Rienharts. Found quite a bit more untapped grunt. But he always does.
Think Hooker makes some two into ones also.
Good Luck;
D.B.
P.S. Only got down to zero last night - so far hasn't been as cold as predicted, but plenty of snow. See what tonight brings.