Most pistol type weapons are unsatisfactory because of the amount of bullets needed to take down a regular foe in Cod4/ WAW (Don't get me started on foes using the Juggernaught perk, for it is 'naught' without pains in the fingers and mind. Pun intended. It would require a whole clip to take down a foe, and more.)
I do prefer the USP (CoD4) and the Magnum (WAW) for solid shooting, and having a strong punch to enemy health. They are very reliable and satisfactory guns, but otherwise, the other guns provide no satisfaction of that level.
On the other spectrum..
The most satisfaction I have ever received from any set of guns in a series or set of weapons is from the Ratchet and Clank series. Name any gun and I'll put it to good use. Nearly every gun in any R&C game is satisfactory (RYNO, I'm looking at you. Although you over-compensate, you do well in my times of need.)
The most satisfaction I have received from an individual weapon is the Mk2 pistol in Metal Gear Online.
One hit to the head and..
-Zz-Zz-Zz-
(The enemy has fallen asleep, due to the fact that the silenced pistol uses tranquilizer rounds. No flashy, loud bang or explosions. Just silence.
Perfect for stealthy maneuvers, the way the game is meant to be played.
..Did I mention that it is possible to fire from across the map and take down the target by a headshot? This is possible because the bullet does NOT phase out in power over a long distance. The knockout power is contained within the round, unlike a whizzing bullet which relies on a damage system from varying distances.
This is what makes the Mk2 pistol so satisfactory. Perfect.)