The SHO intercooler is pretty good. Your concern should lie more with keeping the PCV system, turbo piping, and intercooler free of pooled oil/crud coming from the PCV system. Check & tighten (not overtighten) clamps regularly. Feel around hose ends to make sure there are no splits. Drain the intercooler if you spot any buildup in there. That sort of stuff.
Livernois/PPE downpipes are 2.5" I.D., Unleashed's offering is 3" I.D., stock is 2.25" I.D., IIRC. Be prepared to soak the nuts/bolts thoroughly in Kroil or PB Blaster etc. prior to attempting removal, as they tend to rust into place. Maybe replace them with good stainless steel parts instead (ARP?). Double-gasket the flanges if needed, but use new gaskets. The 3" downpipes might be a tight fit, but they do fit.
If you want to take a crack at the PTU, a good time to do it is when you are swapping out the downpipes, easier with the 2013+ to do so esp if it has the "package".