In the Blitz fair i recently recieved the AC 1 Sentinel, a tier 4 Australian tank in the British Tech tree.
I decided to record my first few games in it and i'm so glad that i did!
The AC 1 has an extremely good rate of fire which is made all the more lethal if you have the fast reload consumable, the gun penetration is decent enough for its tier however it has a relatively low alpha damage.
This is made up for ,of course, by the rapid rate of fire which will quickly whittle down any opponents
Have a look at the Gameplay and make a decision on it for yourself, but i think you will come up with a similar conclusion to me... This tank is definitely on the OP spectrum
Enjoy!