stinky, that is the method I use as well. its never failed me and never given me a hermie. And I have done it even 5 weeks into flowering!!!! However yeah, 3 gallons is quite big and I would only transplant if you have noticed growth stunted or if the leaves are cupping down and curling under. If all you see is roots coming out and the plant looks perfect, dont touch anything. If youve got roots pouring out of a 3 gallon pot, your gonna have a nice plant (more roots = more canopy = more buds). Do you let the water run out of the drain holes? How much if so?