[SpecB]

I may know a guy......

The twin scrolls are great cars can see up to 300BHP fairly easily and reliably however they use different turbos to the impreza so simple upgrades are harder over 300.
The Auto box is actually pretty good (We have a 2.5 N/A Auto outback) with a manual override which makes it a semi auto. I run the 3.0r (Spec B trim) as my daily and it's a lovely engine (mins the 6 speed manual though).

I'd take my Legacy over any incarnation of my Bugeye from the std spec to the 400+ animal it became. The legacy is far more comfortable and the interior finish outshines both the Impreza and the forester (Foresters are the same floorplan as the imprezas so actually apart from headroom no bigger than an Impreza) - I'd also choose the legacy over a forester BTW (We had one of those too and my dad also has one).

Issues to look for:
Exhaust Y piece rusting through - stainless off the shelf is expensive and hard to find so either mild steel replacement (Gerlach on eBay) or custom is the way to go. Drop links - consider these almost a service item especially the rears! If you can get a Spec B version (GT-B as a turbo) the bilsteins do start to knock after a while but can be had from Martin (Hallie on UKLegacy) for a very good price (£530-£540 depending on spec). Other than that if an import rust if not undersealed and re-map for UK fuel. I'm happy to show you around the 3.0 if you want and you can see what the Auto is like in Sians car as well (Outback but same box). Stereo upgrades re a total pain as you need to replace the A/C controls as it's an integrated unit (£250-ish for the adaptor kit for the dash).