For my heart: German Leopard II (A5) simply because it looks really cool. Russian T90 because it looks like a "proper" old-school cool MBT. And of course the PL-01 MBT from Poland because it looks like something Batman would use.
For my head: Best ever (modern/GEN3) MBT is without a doubt the British Challenger 2 (FV4034) simply because the only thing that has ever killed one in battle is another Challenger 2. It's gun and armor and all-round battlefield capabilities place it far and away above the American M1A2 Abrams. In one verified battlefield incident a British Challenger 2 was hit by multiple grenades, 14 (fourteen!) RPG hits and even took a MILAN anti-tank missile in it's stride. The crew remained safe inside, the Tank was recovered, repaired and back in operation 6hrs later. In another MOD reported incident a Challenger 2 near Basra was hit by a total of 70 (seventy! good googly moogly..) RPG and lived to fight another day. The British Challenger 2 is basically a Titan, at this moment in time nothing comes even close.
