re: 380 Owners: Walther PPK or S&W Bodyguard

MM,
I suspect you've never shot any of the smaller 380's. That's ok. Anyone who has shot one would tell you:
380's are not as much fun to shoot as larger guns. This is a function of the type of guns most 380's are chambered in--ultra small and light guns that will fit in one's pocket. Pocket 380's have a LOT of muzzle flip to them.
380 range ammo is about 40% more expensive than is 9mm (using Wal-Mart Winchester White Box prices for comparison).
At the stores I've seen, 380 ammo is nearly as hard to find as is 9mm.

If you want a 380 for truck carry/range use only, get a bigger one that WILL be more enjoyable to shoot. In that case, I'd nominate the Bersa Thunder. The Sig 238/Colt Pocketlite are VERY nice guns, but to me they cost a lot of money for a range/truck gun.

For a truck gun, I'd get a serious self defense round, at least in 9mm.