As I explained and as you saw, MARS 15 was one of the last vehicles that just about made it in time for the update
Had it not have been added, there would have been no true domestic French ground vehicle this patch, after people made it clear they wanted one badly.
Any bug report will be forwarded to the devs and reviewed in due course.
The retractable wheel function is not a bug. By design it is intended to be this way as in game, due to the way wheel vehicles are modelled, there would be no difference between 4 to 8 wheeled handling.
So as of right now, that would be a purely visual thing with no in game benefit. If the system changes, then the feature will be reconsidered.
Reverse thrust becomes more and more a very important feature of several aircraft that are possible in the future.
Not being able to land in general on shorter fields (as they don't have drag chutes) I would say is pretty important.
Right now it effects nothing but the EBR. Nothing close by too.
As I said, we dont have the feature right now because it would have no impact in the current game terms. If things change, it will be reconsidered.
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