We have around 1000 of part and would like to make the udf for some features
Please suggest whether the UDF to be placed dependent or Not dependent.
If we make Dependent udf will it slow down the process.
What is the best practise
This is debatable. But from what I've seen and personal opinion, UDFs should be placed as independent. In most cases, user would want to have full control over the newly created feature(s).
I disagree with Hatim. We have hundreds of UDF's used for features such as API flanges and the like. Stuff that never changes, and is rev controlled by the Library. We always place UDF's dependent, so that if the UDF needs to be modified, all parts will update with a single change to the UDF.
If you need to modify a dependent UDF in the model, you can always "explode" it, or whatever the term is.