Steve-myers is right, compressing CPU usage and I/O eliminate is more complex than I can say.
Each compress dataset the compress ratio is different, depent on the data organization, but compress/decompress increase and I/O reduce CPU comsume, so the total CPU time difference is not much.
1) Did you face any issues when your shop started using Extended format datasets?
--> If you using AP program like COBOL or C to process an empty extended format dataset, notice not use random or dynamic processing to load a file, or you will have VSAM open status 30 error.
2) Any points that you think we consider or any issues that might crop up afterwards. The manual says that in case of Stripping the performance is best with only one program at a time, but we have multiple programs accessing the datasets.
--> Sorry I don't know this criteria, but striping dataset process by multi parts of a dataset, it may be downgracde when multi program process same stripe data in same volume. But I think PAV volume can eliminate this situation.
3) In case we do not compress the data, would there still be any gains in terms of performance.
--> For striping dataset, yes, for non stiping extended format dataset, no.
4) Any products that you or others know that do not support these datasets IBM File Manager etc. I know that DFSORT supports them. Though I did not find any specific reference to Extended format datasets in SYNCSORT manual, I am almost certain that it supports it.
--> In my image, no. By the way, we using DFSORT, DFSORT have self performance tuning, but not sure SYNCSORT.
I think you can using extended format like normal dataset except first point previuos I talk about.
Hope this can help you.