As a straightwalled case which headspaces against the mouth, the 40 could best take advantage of a tapered crimp, commonly refered to (in my experience) a "factory" crimp.
By accident I discovered last week that RCBS is now supplying taper crimp seaters with their carbide 45 ACP dies and so too apparently also w/ their 40 S&W, etc. (They must have gotten the message.) So separate crimp dies may now be gilding the lily.
Conversely, light/medium recoil bottleneck cartidges (e.g., 223 Rem through 30-06 & beyond) headspace on the shoulder and can be run w/o any crimp at all using standard neck tension. If a crimp is
used on those latter cartridges, a standard roll crimp on bullet having a specific crimping canelure is more than suitable.