For DD and towing I would do twins. I really love how smooth the power is with the twin set up vs a single. My 4094 billet pulled great in the mid range, but lacked on the top ( stock injectors) end and was laggy on the low end. Twins pull hard from the bottom all the way to the top, very smooth.
What I don't like about twins is all the pipping, clutter, moving shit, relocating the battery, and all the other mess. Also makes things a bitch to work on with more shit under the hood. I still haven't relocated my second battery, its been pretty cold here ( lows under 10 deg) and the truck still starts. If it sits for a week or more I have to jump it. I've got my second battery in the back seat with a set of jumpers in case I get stranded. lol
Like said before, weigh all your options of what you do with the truck, then make a decision. In world of turbos you can't have your cake and eat it to. You have to sacrifice something to improve something else. There are pro's and con's to every set up, decide which you like.