Interesting, we've found if they have been constantly fat they are tough. A thin 2 year old that has lost her calf in spring, had a good summer and a few weeks of 15 lbs of barley will have what we call "new meat" and are very tender and tasty.Cull 2 and 3 year olds are a fine substitute. Just gotta get the ones that are in, and have always been, in good condition. If they've always been fat and happy I would about guarantee they'll be excellent eating if fed right thru slaughter. And big steaks.
I work em up to 1.5 to 2% bodyweight in corn for 45 to 60 days when doing cull females.
Many will frown on the idea.