What?
OKW has no units that are useless because they are hard to vet up. A Sturmtiger does not need any vet to 1-shot medium tanks or whole squads without warning from outside of line of sight or through a bush. A Luchs does not need to be vet 5 in order to be worth it. It is already as fearsome as a T70 while being more survivable for a lower fuel price tag. A stuka does not need vet to obliterate enemy positions etc.
That doesn't mean that vet 5 must stay impossible to reach. We are not discussing how effective units are, the topic is that it is not possible to reach vet 5 on most units, unless you comp stomp for hours.
A sturmtiger that acutally can reach some vet ranks and thus has a decreased reload time can turn out the be a favourable choice if you have to decide between a panther, stuka or sturmtiger.