Help with choosing Prem tank (World of Tanks)

Bought just Heavy Tank No. 6 , under article looked like the rules, armor is a gun is normal, but as it turned out for me it's not playable at first he did not grace throws even eights, 145 mm penetration BB can't penetrate even KV, sew it all and Sundry, even with such a thick for the sixth level of the armor 100/80/80. What is the same Prem tank it is best to change this shit? More inclined to СУ100У or the Dicker max.