Your Subaru suspension includes four struts that not only dampen suspension movement, but also are a critical load-bearing part of the suspension and steering. The stock Subaru dampers are good, but an aftermarket item will have extra features above and beyond what the OEM strut offers -- some, like the Koni yellows and the KYB AGX, have adjustable damping, for example.
If it's just a budget replacement strut you are looking for, the KYB Excel-G for Subaru WRX provides a factory ride quality, but at a value price.
Terminology note: A shock absorber and a strut are basically the same thing, but a shock absorber (or just "shock") is not a structural or load-bearing part of the suspension, and a strut is. For our purposes, we sometimes use these words interchangeably, but technically all Subarus have struts, not shocks.
5x100 5x114 BL BM BP bumpstop GC GD GE GG GH GR GV SG SH SJ VASTI VAWRX
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5x100 GG
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5x114 5x114x GR GV VASTI VAWRX
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5x100 GE GH GR GR-2 GV
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5x100 5x114 BL BM BP GC GD GE GF GG GH GM GR GV SG
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5x100 GR-2 SG
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28313AG020 28313AG030 5x100 BL BM BN BP GE GH GR GV SG SH SJ
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5x100 GD
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