It would have performed just fine, I think. As others have pointed out, its advantages in vision (most Leo 1s had at the very least IR night-vision gear, and later models had thermal imaging) and fire control (full stabilisation and a ballistics computer) would have ensured it a good chance of getting the first hit on anything that came along, and the L7 105mm gun ought to have an an excellent chance of killing whatever it hit right out to its maximum range.