Like Im'DLytFull said, answers to this are going to be opinionated. Personally, I don't think a toy being waterproof is any better than a non-waterproof toy other than it being safer to clean with water. I like laying down when playing with my toys so I opt for laying on my bed rather than standing up in my shower and I don't have a tub. And I've heard some waterproof toys can still go a bit wonky after being used with water so I'm not entirely sold on the 'waterproof' idea anyway.
To each his/her own I suppose.
But I still want to get the Wild G, waterproof or not.
In my personal opinion, water proof is better because it makes the toy more versatile and cleaning is easier. You can simply wash it in the sink or shower if you like, without worrying about keeping water away from a certain area.
But, like "Im'Dlytfull" said, it's a matter of opinion. Some people may prefer toys that aren't water proof. It's all a matter of preference.