I have one and I can say yes it does engage strong....harsh is more like klunk....as in klunk when it down shifts. Upshifts are pretty clean and noise free...about like a well built 727 shifts.
Remember that these things are built to handle thousands of HP so they probably have to engage firmly to handle that kind of power. I believe most of the big name drag week cars run GV's and they are well into the 1500 hp range now.
I have talked to GV at length about it and my set up and the assure me it is not an issue and normal in many cases.
Other than that...slightly annoying issue its awesome. 3:55's and big block that loves expensive fuel and It gets decent mileage on the highway at low-mid rpm's. No problems running 70 all day long.
Someone commented about driveline angle and that can be a major concern. Some cases may require that you cut the perches and slightly rotate them to obtain more neutral angle.
Less than 3 degrees is optimal.