S&W revolver? 'Cause from what I've heard, their auto-loaders are horrible. Fabrique Nationale is a name brand, they make the P90 and several other arms, as well as being from Belgium, from what I've read, the only reason they are not widely used yet is the rounds characteristics. Apparently, instead of fragmenting on impact, the round is designed to penetrate about an inch, then tumble end-over-end inside and leave a >21mm hole out the other side (the rounds vertical size). They are rated to penetrate modern body armor (titanium and kevlar) at 100 meters, and the older style body armor at 500, but government agencies are skeptical of the unarmored penetration. From what I've read anyway.
