I have just completed the SIDS on my 210. It seems as though operators are ignoring the requirement for the SIDS to be completed.
I reckon some operators may be thinking that because they are maintaining their machines on Sched 5, this means they dont have to comply with the manufacturers maint manual which is incorrect.
The SIDS are quite comprehensive so the maint org won't be able to complete them overnight.
Add to this the fact that a lot of these aircraft have been operating in harsh environments, you can expect to find and have to repair corroded or worn parts.
Expect then long lead times on parts from Cessna..
CASA will mandate the SIDS in my opinion just as they did with the 300/400 series.