clifford ig 750, 770 differences?

I have read descriptions of these two security systems and can't find any difference. What does the 770 have that the 750 doesn't? Thanks,

Either relay driven locks or extra sensors.

Reading the install instructions for both, they have the same relay requirements for locks and they come with the same sensors.

The 770 was a later spec with different supposedly better remotes, also (though I'm not sure) the 770 might have a Proximity sensor as well, if so it's many times better than the 508d, more stable and you can adjust it from the remote. The best version is the 950* with internal relay driven locks and a prox or the AG 5.5, same but with a remote start. That's the best selling alarm in the UK, sold as the 650 MkII, insurance Cat I (legally required in Europe) and bullet proof.

As a further comment, the products mentioned are CLIFFORD not badge engineered DEI, Viper, Python, etc. And are markedly better and easier to program than any other product. G5 is all that's left of the original Clifford product.