The GMB water pump is higher quality so it should last longer than the 18 months of the cheap Chinese topcn WP.
The GMB water pump has a metal (aluminum?) impeller rather than the plastic or composite of the cheap Chinese topcn WP that only lasted 18 months before completely seizing. The cheap WP was the bolt through the camshaft type and when the bearing seized, the bolt no longer held the WP tightly to the cam and started leaking in that area. The new GMB WP slots into the cam, without the need for a cam bolt and it also has the traditional weep hole that the cheap one didn't have. The side-by-side photos show the GMB installed with the weep hole comparison and the cheap plastic impeller. Sorry I didn't take a pic of the metal impeller, which had differently shaped vanes and didn't have that wide plastic piece that I suspect was needed to strenghten the cheap plastic.