I know it's been asked before but I'm looking to see what test pipes and exhaust setups are in interchangeable with my awd 3.7 qx50. From what I gather, g37x coupe test pipes, mufflers, and y pipe is a direct swap. Mid pipe is 2" too long. Is that correct?

yes

I would also like to find out if the isr y- pipe awd is direct replacement for the qx50. I have a 2016 qx50 awd. For what I researched it looks like a direct fit. The one I looked at was for the g37 awd. I compared mine to the isr y pipe looks like it should fit. Also I would like to get a Megan racing axle back exhaust because it’s sounds petty good plus it is stainless steel and it looks like direct fit for the qx50 if that’s right. Looked at the model for g37 awd. The muffler looks like stock fit. Not looking for anything crazy. Just something a bit better then stock. Maybe a couple hp would be good too. I have some suspension braces installed already from g37 braces here are some pics.

isr y- pipe will fit.