Before you buy Panzerblitz, I would strongly recommend Eastern Front
Tank Leader (EFTL) from West End Games instead.  It was designed
fifteen years after PanzerBlitz, and it shows.  The system is
smoother, integrating weapons performance, troop quality and morale,
and command control (which PanzerBlitz knows nothing of) in a simple
and elegant system.  Tastes differ, but I have not touched my copy of
PanzerBlitz again after buying EFTL.
 
EFTL is on roughly the same scale, with no more complexity, than
Panzerblitz, but uses a unique system to represent the superior German
command control structure.  In Panzerblitz, Russian counters represent
more tanks than German ones to arrive at comparable combat values.  In
EFTL, you can actually see Russian numerical superiority and the high
fighting power of their tanks.  Their historical disadvantage was that
the Germans were usually quicker to take advantage of a situation
(note that this has nothing to do with tank speed), and this comes out
beautifully, while the Russians profit from concentrating their forces
and from the capability to regain the initiative through use of
commands originating from higher level headquarters.  The standard
scenarios (with tanks only) take about an hour to play, the larger
scenarios (with infantry, AT guns and artillery) take from two to four
hours.
 
The Designer of EFTL was John Hill (designer of Squad Leader), and the
same system is used in two other games, Western Front TL (featuring
the British and Americans instead of the Russians) and Desert Steel
(Germans, British, and Italians in North Africa).