On 4v4 you MIGHT have to build it outside the base, take Semois, Kharkov, Moscow, etc. All maps on which you build it INSIDE the base.
That's the moment You use walking stuka.
Axis can counter B-4 with single arty strike, stuka bombing, le FH, and many different ways. All you need is to choose doctrine with counter or use your skills. On the other hand, killing Jadgtiger is many times just impossible even with combined arms. I just button, mark target, FAB50 bombing strike, 2 ISUs and Jadgtiger was able to reverse.
My pont is, you have 100% chances to hurt B-4. It will be crew wipe or destroying B-4 and yet many axis players are crying that it cannot be countered.
My advice, take soviets and try to counter well-microed Jadgtiger without B-4.