You aren't the only one with this issue. The AEM v1 is not a fan of the stock CPS. Options are to crack it open and do some soldering to run hall sensors, or change to a different standalone.The main issue I had was the tuning with the AEM EMS. The 7M ignition system did not work well with the EMS causing a low rpm stumble
Regarding 7M vs 2JZ: I got a 7M shortblock in good shape for $50. Add JE pistons, some rods, etc, and it's still cheaper to build a mild forged 7M vs buying a stock unknown condition 2JZ around here.