Also, in regards to the SP-01 mag springs seeming 'weak'. The 18rd SP-01 mags use the same factory mag spring as the flush 16rd CZ-75 mags. They don't make a longer mag spring for the SP-01. Because of this, I put Wolf +10 extra power CZ-75 mag springs in all my SP-01 mags. I also keep my mags dry. I still view the 18rd mags as more of a 'competition' mag for gun games, so for occasional carry and HD use I prefer the flush 16rd mags.