The health of course is one of the big difference, and since both are being used by a combat character, they spawn at level 90, but I think you can see a decent increase in combat effectiveness.
The real benefit though is in the specials. What I did, is created a 3rd combat toolbar to switch to that has all my specials in the same place, but replace the non combat boxes with the droid specials.
I'm still a novice DE in this regard, so I may recraft one with the higher level specials, but I'd say this is a good example of the power of the new combat droids.
I even threw in a harvest module for fun, lol.