Need Help! Short tube vs Long tube, what should i get???

I have a 2011 Tacoma 4.0 v6. I am looking to upgrade my headers since it's almost Christmas time and I'm ready to get some new ones (want better performance and hate looking at my rusted out stock ones). I do have a couple questions. I would like to get Long tube headers (more high end power) but am concerned I will have to possibly get a Y pipe?? That's what some people are telling me and I'm not too familiar with exhaust systems. I tried my best getting some pictures of my current exhaust setup. It's all stock besides a magnaflow cat back muffler, but if anyone can help me with advice, Doug Thorley vs JBA, what route I should go, etc I would appreciate it! Thankyou!

 

Long tubes you don't need a y pipe unless you want max flow