Not so much about being equal more about making a difference. At the low speeds and low loads (compared to, say, the wheel bearings on a 6K lb. trailer tooling down the highway at 65 MPH), I doubt there will be a discernable difference except when it comes to viscosity in the extremes of heat or cold.

I use marine bearing grease. At $4 a tub it works fine and should last many years.