Thanks pmb0186
I'm still leaning towards the Edelbrock 1901 for the annular boosters over the street avenger / summit. At 500cfm, it's plenty large enough and with those annular boosters it should have better low-mid rpm perf where it will be 95% of the time.
the summit has annular boosters (for street avenger it's a relatively expensive upgrade), and pricing wise is slightly less than the Edelbrock, but also probably has limited support here in Aus even though it takes holley parts.