Adding Ionic v4 components in Ionic v3 app

Goal here is to do an incremental update or incremental adoption of newer Ionic4 components while letting the larger app (including navigation) stay v3, for a while.

Ionic v4 can be added to an app just by including it in html, like this:

<link href="" rel="stylesheet">
<script src=""></script>

If we do this in a v3 app, my concern is that some of the ionic-component names are common between Ionic v3 and v4. Which is likely to cause confusion/errors.

Has anyone tried this? Is this is likely to fail magnificently and not even worth trying, or can it mostly work if done with some care?

Can it be worth the effort to do a custom build of Ionic v4 where all v4 component names are prefixed like <v4-ion-button> etc… to allow for easier and incremental migration/adoption of v4 in larger apps?