I kind of expected the Tiger to be even larger than the Panzer III than it is from looking at photoes of the real things, however, Im too lazy to take measurements to see if the sclae is correct on both.
HLs line up in size from smallest to biggest is like this:
Pazer III/StuG III
Panzer IV
Tiger I ~Panther~Jagdpanther (Im under the impression HL Panthers use the Tiger chasis, so they should be pretty much the same size, not sure about the JagdPanther)