If you can get the Hero3+ on sale, grab it. From what I've read, the Hero 4 will be released in June, but its primary differentiator is more shooting levels at 4K (I personally don't see the use at this point). It will have a different lens to help in low-light situations, but IMO, I don't think it's necessary for the average user and family. I've been really happy with the Hero3+ and see no reason to upgrade to the new model.

My only complaint is that the LCD menu is not ideal. I hope a future release has a better interface/menu that's easier to read. You have to view it at the right angle. I find myself making the necessary adjustments through my phone and then heading out.

Great device though - we are definitely having fun with it.

Smooth travels!