Taunt is the superior move of the three, but it still manages to be my least favourite. I always enjoyed using Sweet Scent to automatically trigger an encounter, but I didn't do so enough to care for its loss as TM status.
Now, Water Gun...I love that thing. I would use it on Rattata, Clefairy, or more often than not, Jigglypuff to help on my trek through Mt. Moon. Not having to rely on just my starter to get through those Geodude's was great. Plus I didn't feel bad using it and replacing that move later. --- I like Monster Rancher.