Well, a stretch goal was revealed today for some Kickstarter-exclusive figures that can be used in solo mode, and the update announcing them says that they "will not be present in retail stores or online". That suggests there will be a retail version, but I personally can't say for sure if or when such a retail version would be available. We know that the Kickstarter version will be made though. So IMO, the safer option is to back the campaign. That's generally been my view for crowdfunded projects though -- I don't count on there being a retail version, so I get it when I can. Also, it seems common for the Kickstarter version to be cheaper, so getting in early often means getting a discount; I think that's worth factoring in to your decision as well. I hope this is of some help.
Thanks, but it also depends where you live as sometimes it is more expensive then say if you were to wait for retail in your country.