How quickly do you need the kits? I say this because if you keep your eyes open at different vendors' sales lists, you'll find more updated kits by AFV Club and DML for not too much more than $20 (less shipping of course) but are stocked with accurate tracks and PE and such.
For instance DML's versions of the M4A3 and Jagdpanzer IV are light years ahead in terms of accuracy. AFV Club, Tamiya andItaleri/Testors each have a Sturmtige -- and are accurate in that order too. The JS2 by Tamiya is a gem.
While $20 may not seem too much, if you're a stickler for more of the modern bells and whistles, it may be better to shop around for a $25 DML Jagdpanzer IV or $28 AFV Club Sturmtiger that go on sale than jumping into the Testors boxings. Just my two cents.