OK!
A subject that im totally into for, i think obvious reasons.

EJ25 - normally aspirated motors that can be found out of anything from a 2.5 RS to a Outback. The years to look for would be 2000+. 98's were DOHC and were a nightmare on overheating. 99's a bit better, is when they went to the SOHC aka: Phase 2 motor.
EJ205 - usdm wrx 2.0 motor. Every year of these is good.
EJ255 - Turbo Forester and Baja motors. 2.5 liters.
EJ257 - usdm wrx STi motor. 2.5 liter. AVCS and a few other goodies over the wrx.
EJ207 - JDM STi motor. AVCS, sodium filled valves, bigger valves and an 8K redline!
Can't quite remember the number for the new Legacy and Outback models. Might be a 255. I should just go outside and look.
Personally, i would stay away from anything JDM just bc of parts availaility. USDM will get you just as much power and if something breaks, just go to your local subaru dealer and order parts.
another option for not a crazy price would be to get a EJ257 block and put a set of heads on it. Virtually almost every head listed above will fit onto the motor without a problem, just get a head gasket set for the 257.
I have done many swaps, none to a 914 just yet.
EJ25 into a 95'L that was a 1.8
EJ20 into a 98' RS then put in a full EJ207 swap.
EJ20 into a 98' Outback
EJ20 into a 95' L
EJ20 into a 01' RS
EJ257 into 2 95' L's
etc.etc.etc.
check out my list
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