What stepper driver should I choose?

I am trying to figure out the best stepper driver to use for my stepper motor. The motor parameters can be found here

http://catalog.orientalmotor.com/item/all-categories-legacy-products/tegories-pk-series-2-phase-stepping-motors-legacy-/pk296a2a-sg36

I am going to be using it in the Bipolar configuration

I = 2.1

V = 2

R = .96

I tried the L6470 which did not work with this motor. The torque was bad even at low speeds and the chip got really hot.  I am new at trying to match a driver to a motor so any help would be appreciated.