Mike
I have GSH in my ponds. There are pro/cons to GSH just like all the stocking choices. I'm pleased to have them in my pond. The initial fathead minnows were gone in short order. The GSH are much better at eluding the predators and seem to be maintaining their numbers. They are working well in my situation. I'm relying on the GSH and native BG as prey for the YP and LMB. I'd like to believe I've been getting the very good growth of my YP with the GSH as a bonus prey species.
I've not seen anyone on this board or anywhere else ever suggest to wait to begin stocking fish. The only delay would be for the predators which you already understand. Maybe fish prices are depressed right now and he wants you to wait to buy fish until prices go back up

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I can't comment on the pellet taste but.......One thing I do know there sure are alot of people on this board who feed.
Since I have my tinfoil firmly in place these days

.....Let me understand: A)being suggested not to feed. B)GSH are not popular. C)Is this guy pushing hybrid BG also? Sounds like he is a great businessman!! Setting himself up with a customer for future sales? A self-sustaining fishery would be bad for his business. It appears you are choosing to be an educated consumer. We are in the minority so he'll do just fine with the majority who take the sales pitch at face value.
Chuck