I run a Aem v1 Ecu mapped at 600bhp running 880cc sard injectors and does the job with no issues, Supra engine management is old technology and your goal can be achieved using a ecu like G4/haltech etc . Syvecs gives you more control on transmission /traction control it has the ability to monitor oil/fuel pressures etc and also can change injector duty if fuel pressure drops so it controls the engine more safely,but you can achieve this my monitoring your gauges and right foot.newer cars with driveby wire and canbus then Syvecs is one of the best Ecu's to have
Injector wise ANSU will be my choice which are bosch injectors rebranded they have less lag time which makes them easier to control and map, a good mapper will be able to map any ecu like ryanG did before becoming a director of syvecs