Over all, I have been carrying a concealed firearm for close to two decades. During that time I have owned, shot and carried pistols as small as a Freedom Arms .22 and as large as a Ruger Blackhawk in .45 Colt.
I spent most of that time with pistols the size of the S&W 4006 or the P229 Sig in strong side belt holsters. However, I have carried in about every rig from ankle holster to shoulder holster. I learned that with the proper garments and carry rig you can conceal almost any pistol or revolver.
About 8 years ago I purchased an A75 Astra in .40 S&W and learned to enjoy packing a more compact size weapon. Three years ago I upgraded the chrome plated Astra to a K40 Kahr with night sights and wood grips. Still I felt that I needed a concealing garmet to really hide from an educated eye. I was already in love with the K40 when I saw a slightly used MK40 Kahr with night sights in a dealers showcase.
I had been tinkering with an AMT DAO Backup in .400 Corbon. The AMT Backup carried like a dream in a pocket holster or an IWB holster with an untucked T-shirt or polo shirt. It had plenty of punch but my trigger finger was starting to get muscles!! I knew I was ready for a more compact pistol about the size of the Backup but without its horrible trigger. The MK40 filled all of my needs.
It is a true sub compact pistol, stainless steel, night sights, fantastic trigger and an accuracy level equal to some of my best full size weapons. I have been packing an MK40 with night sights now for several years and its true love. I know it sounds crazy but the only thing keeping me from buying an extra one to stash away is the feeling that an MP40 may be on the horizon someday.