Yep I understand that, I do have a question though.

Does the SLU retain the Heng Long track recoil?

Bascially, I would be wanting to retain it but have the option to disable it. For example say if I wanted to use the SLUin the StuG, I buy the Panzer III/IV SLU whack it and because the StuG has a fixed casemate want the tank to recoil along it's tracks. Not quite as violent as the standard track recoil but I would still want it.