DD,
Yes, there is a good reason for using wind down. Wind up is fine for calculating heading from desired track, which is all you need to do for PPL. But when you come to the ATPL exams, you'll need to do other calculations, e.g. calculating your track from your heading, calculating the wind from your heading and your track, etc. etc. etc. These can only be done with wind down.
So learn wind down now, and save yourself a lot of hassle later on! It's only slightly more complicated to calculate heading from track, but it'll make things much easier later on!
FFF
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