Exploitation? Not even close.
Most exploitation films (which is pretty broad... think extreme Horror/crime/sex/race movies and you'd get the idea), that eventually were shown at Grindhouse theatres, were made on shoestring budgets and usually with a cast of complete nobodies.
Tarantino and Rodriguez made each of their films for several million dollars using top stars of today.
Kinda defeats the purpose don't it?
The best thing about the movie were the fake trailers.
Rodriguez's PLANET TERROR was fun but brought nothing new to the table and Tarantino's movie was awful.
The dialogue felt like it was somebody trying to be Tarantino and not QT himself.
The car chase was good but nothing to write home about.