The KPZ 70 is a very good Tier IX tank, the gun is one of the best at Tier IX if you consider the large caliber, it has a very strong turret which makes hulldown very easy, 7° gun depression and very good mobility. Yesterday I did 6822 damage and 4 kills with it in the 4th round. And it just looks mega sexy!
For the progetto 46, you actually don't want to "stay away" from shell 1. Since its the last shell in the clip, you do't need to factor in the 2.5 seconds extra. In conclution shell 1 has the best rate of fire (and dpm) as you can see bellow; Shell 1:6.4 sec Shell 2:7.5 sec Shell 3:7.5 ses Have a blessed day!
Styer is super fun when it just come out, i play like assault glass cannon and bully mediums. But nowadays, given how many smasher there are, this tank is not fun, and it's very team dependent, so yea