Let compare some of the main pros and cons
-GTM kit comes with Pre-Bent Stainless Steel Heat Shields Greddy does not offer any heat shields over the manifold
-GTM Bar and Plate Core Intercooler vs Greddy tube and fin core (bar and plate is proven to be more efficient )
-GTM Ball Bering water and oil cooled Garret turbo VS Greddy journal bushing type turbo and oil cooled only (ball bearing turbos spool faster,more efficient,have a much longer life span and for the 370z oil temp issues going with water cooled turbo is no brainer.
-GTM kit does come with tial 50mm blow off valves VS
Greddy No blow off valves are supplied.
-GTM kit is complete with fuel and engine management VS Greddy does not come with neither (have to by separate)
-GTM engine managemen is plug and play (via flash ) Greddy is piggy back system required cutting splicing engine harness.
-GTM kit has a lot of room to grow (6 different turbo stages 9 different a/r ) VS GReddy has one turbo option only available.
-GTM kit cheaper and has better value, you get more for what you pay for VS Greddy
-GTM offers 2 different couplers colors VS Greddy only one
-GTM offers k&n filter VS Greddy foam filters
Sam