/6 Exhaust: Dual or single? Your thoughts

Just like the title says, I know it's not a big deal, but I have been thinking a lot about this. What do you think is best? Dual or single exhaust. I have a welder, a y pipe, lots of Pipe size choices, and use of a pipe bender. What size pipe is best for the /6s. I'm running the 170 for now to see what kind of trouble I can pull out of it. 27k miles all original.