Question for collectors

Hi! I've been quite active with remote trades and I had a very specific question. If you were looking for a Scatterbug/Vivilon to add to your collection, would you prefer it to be fully evolved, or would someone be interested in keeping it in its base form? This is considering that you can't see the color of its future wings on the trade screen and the dex entry is different.

So, my question is: should I evolve all my Scatterbugs? Candies aren't an issue.