Generic Delta

Hi SAP Guru,

Iam haivng a doubt, there is a concept called generic delta in the R/3 side, i.e at the data source. while creating the data source itself we can create a genric delta on a particular filed in the R/3 side. We also have a delta maintainance in BW.

My doubt is that suppose if we have an ods, and its corresponding r/3 data source is having genric delta, then

which one is better is it the r/3 side on or the bw side one.

Thanks in advance,

Dilse...

Harish