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Not always. Some EFI systems (speed-density) are designed strictly for one particular engine with specific exhaust system and other parts. They can regulate the a/f ratio only within a relatively narrow range. Most of it is pre-programmed. I would think if you put that system in a bigger or smaller engine it wound't run well, maybe someone has experience with that. The automaker will put different computers (or chip) in for each model. The oxygen sensor is used to fine-tune the end result, but O2 sensor doesn't work when the engine is cold or at wide open throttle.

EFI systems using MAF (mass airflow) sensor generally can work well with engine modifications, like if you put a different camshaft in. MAF directly measures the airflow coming in, and so the computer can figure out what the a/f should be (not pre-programmed). Again the oxygen sensor fine tunes it. I think these system have a speed-density map also in case a sensor stops working they still run.

So yeah, I've never driven a carbureted car that ran as smooth as a good EFI system. But if a sensor goes out, EFI can run poorly. I once drove 1000 miles with a bad TPS. It made the throttle jerky and put a big black smudge on the back of the car above the tailpipe. But it started perfectly and never stalled. And the beauty is the engine diagnostic told me which part to replace -- no expensive tools needed.