Toe covers versus shoe covers is completely a temperature related thing for me and only when riding in the road. I wear neoprene socks for mountainbiking when I might be walking in mud.

I adore my Bergamo (Capoforma) toe covers which have a wonderful ankle wrap. Except for Castelli, I have not found women's cycling tights which cover my ankle bones leaving a cold area. These are great for when shoe covers are far too warm.

I wish TE would carry them.

http://www.uplandsg.com/capoforma/NeopreneShoeCover.htm

I don't know where the size chart is, but the small does work with a size 38 Sidi even though the chart indicates it is too large.