Dont tend to use area SAMs much anymore but would say it generally works.
Ignoring firing at a plane as it arrives the SAM will not fire at planes or helos under its min range.
Does work I have exploited the min range with helos.
Latest SAM I have used Canadian ADATS system with a min range of 20. Refuses to engage anything below 20 with it but otherwise works fine vs ground & air targets.
Nifty buying that air defence when he bought no planes was not such a points waster after all.
If only they had giros