I've had mine about 18 months now, and I think they are probably as waterproof as you'll get from non rubber boot. The leather is thick and water repellent & they are goretex lined. To keep the leather in condition I often give them a lick of G Wax.
Fishing I've stood up to my ankles in the lake and not had any ingress. I guess in time the goretex lining will deteriorate, but if the leather is not holed they wax should keep them pretty waterproof.
cheers
Gareth