I would go with either the H&K USP 40 or the Glock 23. Both are very durable, lightweight, easily concealable and extremely effective. The Glock is a dummyproof pistol. You squeeze the trigger, it shoots. I consider the H&K a classic pistol. I love German products, so I"m kind of partial. (ha-ha)
Good Luck in Your Decision,
wolf