Yes im running 300+ on a TD04, I know its said to be the impossible but I didn't relay all that's done to my engine either (internal stuff, higher compression). and 02-12 wrx 5 speeds all suffer the same problem. I went through 2 standard gearsets in 2000 miles. Either STI or Rallispec gear swap (What I did).
Subaru are a great platform for high cost. 10k+ build but as all others have said its not something you can cheap on. Ive already got 9500 into mine with a very good base car and ive got another 98,000 till im happy.