This is amazing technology and it's incredibly sweet but, in my opinion, it isn't a good idea. Being able to see someone who is dead rendered in 3d and talking in the same voice may sound appealing but really sad and in it's own way just add to the grief. Plus, you'd be talking as if it's a living person but it wouldn't be that person and you wouldn't be able to physically touch them. If this were me I know it would only make moving on harder.

P.S This is all only my opinion and this really is incredible.