I bought a Canon converter but found it a bit fiddly and time-consuming - lost interest very quickly.
My current canon scanner has an adapter for slides and that is pretty good, although I found it tended to give everything a bluish, cold look. Might have been better if I had upgraded my VueScan software and used that. Still a bit fiddly to use but if you're considering getting a new scanner anyway it's worth thinking about.
Easiest was one of these bought cheaply (used but in good condition) from ebay. Not absolutely top quality but good enough for computer viewing and you can always select the ones you really like to send off for professional treatment or printing.
HOME MOVIE TRANSFER - Convert Your 8mm S8 and Slides to Video DVD Digital | eBay
Very fiddly to set up but easy to use (as long as the projector stayed focused), just sit with the slide projector remote in one hand and the camera remote in the other. You can process the slides very quickly.