Which used Subaru Legacy estate should I buy?
If you'll be doing some off-roading, go for the Outback model, a beefed-up version with extra ground clearance and decent equipment. Don't expect miracles, though, because it's designed for light off-roading, not hardcore back-of-beyond work.
For all other uses, we'd stick with the standard Legacy. The six-cylinder 3.0 (auto gearbox only) needs revving to give its best, but its best is very good. However, it's costly to buy and run.