No, it is different. Photon drives are like a reactionless drive in that you are not expelling matter, but photon drives are emitting mass/energy in one direction and moving in the other and conserve momentum.

Reactionless drives just produce force, pushing off "nothing." They violate conservation of momentum and break physics as we know it pretty conclusively.

They push off the whole Universe. They go in one direction, the Universe - much slower, in the opposite, and thus momentum is conserved :)

I am not sure if you are joking...but one should not imagine the situation like a tiny space ship inside an egg pushing against the egg shell from within.

There is nothing coming out of the EM-drive, it just creates a force, which is why it would be awesome.