I would definitely go for the dual setup, one of the first mods I made to my 55 many years ago, even before my first set of headers.
I'm running long tube Hooker headers and good quality turbo mufflers, and have ran that setup for several years.
Just recently I decided to add an "H" pipe as the "glasspack sound" on a hard romp was not sounding good to me.
The "H" pipe did smooth it out and a much nicer sound I can now really enjoy.
I was sceptical of the "H" pipe, but am glad I did it.
Whatever the case may be, I'm sure you'll enjoy the nice sound of a good set of dual mufflers.
I like my dual exhaust with long tube hedders, 2.5 inch pipes, mandrel bends, H-pipe, turn down ends and quiet dynomax mufflers. And when I want to really hear it I open my electric cutouts and let it really bark. For me, best of both worlds.
"Luck is the residue of hard work."
Thanks for the input guys. Have always been partial to the old Thrush muffler's but I know they are getting hard to come by. Will definitely go with the dual exhaust, probably with straight pipes. Thanks again.