I don't know about the products he sells but I wish he would stop writing about cartridges on his website. Every fool is linking to them even though he plainly hasn't even shot some of the ones he writes about.
Anyway, I am always wary of someone who recommends or condemns using a cartridge or bullet based on the weight of the animal.
I sent him an email once, and immediately was hit with a demand for money as a payment for replying.
I have better charities to give to.
