Over-head braced, also known as headrail braced toilet partitions are the most popular style of bathroom partitions for many reasons.  Price, strength, and ease of installation to name a few.  No special floor or ceiling construction also makes this style appealing.  Wood, concrete, light or heavy duty backing would all be acceptable fastening applications. (see mfg. recommendations)The least set of skill set is also required to install this style of partitions.