IP - Performance of Characteristic relationships

Hi there,

I am implementing a planning application in IP and have a question around "Characteristic Relationship" vs derivation using FOX formulas.

If all of the values I am looking to populate exist in master data attributes, in general is it faster to use Char rels or FOX to fill values into these characteristics?

Are the overhards significant with Char rels ?

I am working on a rather underspec'd machine so am a little unsure about the performance implications.

many thanks

Mark