On the first part, all of them. It takes six shots to kill a Panther, four shots to kill a TD, and the Panther has similar reload times (~5 seconds) to the SU-85 and Jackson. It'll absolutely clobber the Firefly, which takes eight seconds to reload.
Yes, if it's defended by snare infantry and AT guns you can't do that, but the whole isolated comparision breaks down when you bring the full army in.
The isolated comparison does not break down. Being able to engage at a higher range means it is simple to keep out of the way of at guns and inf.
On the other hand having 50 range and having to chase down a kiting TD makes it difficult to avoid inf and TDs.
Because of this For the panther, it is advantageous to flank (unless it hits a mine).
Katov contends that because a 60 range TD doesn't have to flank means that a 50 range panther doesn't have to. And that ignores the above 60 range is a huge advantage.
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