If your not going for a map then an oem one from a reputable source would be fine,
The problems with ours is they are mapped for 100 Ron fuel so it could be a case of it just hesitating due to chucking too much fuel in, before I had mine done it ran very rich to the point where I may as well have just poured fuel down the drain,
I'm nit really clued up with the auto box set up, I'll have a poke around, sorry didn't get chance to ring subaru for a pcv price