I haven't tried a chickadee RS but it looks like they use a gathered shoulder which is comfortable and versatile for most people, although wearers with narrow shoulders often prefer a pleated shoulder.

Ask me again in about two weeks and I can tell you what solarveil feels like. Apparently it softens well with wear and washing.

Solarveil is used primarily for three reasons - one; it is a breathable fabric good for summer, two; it has a high UV protection rating (70% single layer, 90% double), and three; it dries exceptionally quickly, making it excellent for swimming and showering.

Single layer slings are less supportive for larger bubs, but they are great for short trips to the pool/beach, or for wearing in the shower.

It is a discontinued fabric, and is getting harder and harder to find (particularly in khaki and black which are very hard to find).