I'm just going to ramble since I don't know what you wish to know.
Never owned a shorty, bought 4 different SMPL clones (Copper,Black, SS, Brass).
The SMPL is my favorite mach tied to the Slug.
I notice both are hybrids. The SMPL is sleek and the tube lacks any logos/inscriptions/etc; all that is on the button. If I recall correctly it has a relatively low voltage drop, someone did some test in ECF. What I love most about the mod is the button, it has a good throw and never had crunchy problems after months of use. It uses a spring but I saw a few clones that used magnets if you feel the need to have one.