The 325 is the predecessor of the 425. It is, for the most part, identical to the 425. Most 325s I've seen have better wood than 425s. Early 325s have standard Invector barrels, later ones are Invector Plus. GTIs have a "broadway" rib and "unique" stock dimensions. They are an older model. The ones I've seen have standard Invector barrels. Handle both before you buy. Both are good guns.