I used a corona for a couple of years before upgrading to BC last year (bough used from fakr). The carona did the job ok but my efficiency wasn’t consistent and it was a bit harder to sparge since the hush are a bit more shattered as oppose a just crush. Now with the BC I have constant 74-78% efficiency so now my recipes are way more predictable and crushing grains takes me 10 minutes as opposed to 30 minute (even with a drill)
I still use my corona once in a while for raw grains or corn (mainly for sour beers)