There's a world of difference between a rusted barely fly worthy Mig and the "Bison" upgrade the Indians and Israelis created. Case in point the old Mig-21 had

There's a world of difference between a rusted barely fly worthy Mig and the "Bison" upgrade the Indians and Israelis created. Case in point the old Mig-21 had a so-so radar from the start, the Bison version has a state-of-the-art radar able to target and fire at multiple objectives at the same time. And that's just once component of many that were upgraded.