I use both. I know it sounds dumb, but I'll tell you why.
The electric impo cleans between teeth better and it just does and over all nice job. However, I slobber like I have rabies using it. It is insane and really gross. Don't watch me. So.... I also use the manual simply because I slobber less with it.
I’ve used a manual one for years but recently switched to an electric one. I got it for free though as I recently changed to a new dentist and the first several new patients got one as they recently opened up.
I’ve had an electric one for a couple years now and I definitely prefer it to manual ones. Someone mentioned a water flosser? I’ve never heard of it but I’m intrigued