I agree.
Also, i think Puma could very well stand toe to toe with a Sherman, let's compare the costs:
Sherman 340 mp / 110 fu
Puma 320 mp / 105 fu (70 + 50%, OKW fuel income reduction).
Not that big of a difference, the result of such a fight should be determined by microgestion quality of the players involved. The two units are very different in their role and design, so it could very well be 50/50. Do you feel you destroy shermans more than 50% of the time Barton ?
(i used the numbers of the USF forces guide, i don't own the faction, thus can't check the prices of the sherman ingame).
This is true only if you don't converse fuel, conveniently puma gets out of conversion truck.
Also, you can't say it costs more, 70 fuel is 70 fuel regardless of income, because both sides don't sit on 50% of the map whole game, its much more dynamic then that.
There is also teching cost involved, which practically does not exist for the first truck due to starting fuel allowing almost immediate placement.
So yes, the difference is there and its significant.
Unless you want to argue that 5 min puma costs almost as much as 14 min sherman.