I don't know about those brands at all. I will say that you can drill the Weiand pump for the bypass.
It isn't that the casting for the passage isn't there, it was just never drilled. All you need is a 3/8" drill bit and something to turn it and about 10 minutes of time. Other then that the Weiand pump is a high quality pump at around $100.
The edelbrock is around $170.
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