I finally get my challenger line to C1 Ariete (Tier 8)~~~
But other line M1, Leopard, T-72, still at Tier 6...
Long way for research n credits earning...

Great progress bro 

I'm here waiting to buy all Tier 10 MBTs after patch today (hopefully). 

Note that, C1 Ariete is the only MBT in that line with HEAT rounds. And it becomes an absolute beast with the armour upgrade and reload speed retrofits 

XM1 and M1 Abrams feel really bad at that tier (before the buffs), therefore I cant really comment on their performance now.

For the Leo line (before buffs), the Leo 2 (Tier 7) was the worst.    And at Tier 8-9 it becomes stale    The Leo 2A6 has EPIC front armour though 

All my AFVs are at Tier 7 at the moment.