Dave, I have a ProTec bag (kinda half way between a gig bag and a hard case-- they use styrofoam as for the walls). It is very nice, reasonably light, protects well and is durable.
I've had mine for 12 years, and it is still in good condition. My bass fell 3 feet to the ground in it, and didn't even go out of tune.
I like them so much that I bought one for my father-in-law when I bought him a Schilke trumpet (they're like the Alembic of trumpets).
They are great cases.
Brad