VAT refund – is it actually worth the hassle?

I’m travelling to Spain soon and a couple of my friends are already planning on doing quite a bit of clothes shopping while we’re there. We’ll be flying home from Barcelona El Prat (BCN), so I’ve been looking into how the VAT refund works for non-EU visitors.

For anyone who’s actually done the VAT refund at El Prat, how straightforward was it? Did you ask for the tax-free paperwork at every store, or is it only really worth bothering with for bigger purchases?

I’m especially curious about the airport part. How much earlier did you arrive to get everything validated, and was it easy to find where you needed to go? I’ve also read that you may need to have the actual purchases with you in case they’re checked, so I’m wondering how that works if the clothes are going into checked luggage.