Basically, they have no shock value any more. That's probably a very good thing, but it may take some excellent micro for them to stay alive long enough to pay off their investment.
Ain't kiting the easier micro though? "Whoa stuff's getting closer, better reverse". Obviously not game-closing/ruining as the shock lights we know so well (and rushing them into a gap of course had a lot to with being kinda broken), but
conceptually it should be simpler, since getting closer would (well,
should) mean more risk. For example, an M20 that mostly only dicked around soon after being built gets to do nothing else but lay mines and scout for the remaining 25 minutes while a Puma's still got a pretty good chance to shoot at tanks later and survive it.