One of the reasons why I don't like having false nails is because their too plastic, they sometimes just can't do what natural ones can.

I don't think theres any tips out there that feels close to the natural thing. My husband used to slightly complain when I would massage and scratch his back because I wasn't able to scratch deep enough. And it use to kill my fingers trying to do so.
It's been about 6yrs since the last time I had tips so I could be wrong. But coming from my own 2cents worth I think you'd be better buying a back scratcher to get the job done right. He'd probly love that even more.