I have an 07 wrx with about 86k miles. Im running a HKS TBE, SPT intake, and Dyno tune at 240whp/320wtq. Stock oem clutch, stock internals, stock TD04.
After discussing on here and with the tuners, the general consensus is that is you have an 07 Wrx you need these to support VF39,43,48 turbo...in addition to a TBE, and intake if already installed:
TUNE- dyno>street tune