The difference is in the collet barrel bushing yours may have.
They break. If yours has one, replace it with a solid bushing.
The other difference is, yours has a firing pin drop safety, and no hammer intercept, or safety notch on the hammer. Some feel this makes getting a fine trigger job done very difficult. If your trigger satisfies you, it is fine.
Yours probably has a plastic mainspring housing instead of metal.
It probably has a MIM sear & disconnecter, and possibly extractor.
They can be easily replaced with machined steel parts if plastic & MIM parts bothers you.
Otherwise, they will probably still be working long after you are!
Yours has better sights, and is already throated to feed JHP ammo, which the 70's were not.
All this is neither here nor there.
If you love your gun, you didn't miss out on anything by not getting the Series 70.
rcmodel