The biggest difference I can see is the slide serrations. The 9e has fewer but larger serrations, the second thing that strikes my eye it the 9e has a longer sight radius. The 9e uses a viewing port rather than a pop-up style loaded chamber indicated, and the slide on the is angular rather than radiused. It also only comes in one finish, no stainless here!
To my eye it seems the price reduction is mostly in machining. I also like the 9e better, especially the serrations and sights. While round may look more refined than square, I actually prefer the angled cuts. The loaded chamber indicator I actually prefer the raised one. If in doubt wether loaded or not, I prefer tactile rather than visual.
For my money, I'm going with the 9e. ( or the RAP)
That was a good explanation of the differences, the only thing I would add is enlarge on the sights. The 9e has non adjustable or fixed sights. To me this is actually proffered, as I never change them once set. I also believe they are more rugged. Love my 9e, glad I bought it.
Here's the difference:
1. Less machining on the slide, and without the nitride finish. (I agree, I like the 9e's markings better.)
2. No loaded chamber indicator tab (huge improvement)
3. Different sights. No elevation adjustment on the 9e.
4. The 9e comes in a cardboard box with only 1 magazine and no loader.
I own a 9e and love the nomenclature was explained to me as the meaning economy. Like posted above, less machining, no idiot indicator, one mag, and no case. Other than that same weapon most parts interchangeable. Sites could be better but all in all great gun
The sr9 has a nitrided slide where the 9e is a blued slide. To me that would be the only thing different that would matter. I'm just not a fan of bluing, for some reason I guess the oils on my hands are highly corrosive and if I touch a blued gun and don't wipe it down with oil almost immediately it will show signs of rust within a few hours.
jmiller216; know what you mean, once on a hot sweaty day I rusted a 1911. Haven't had that problem with the 9e yet. When I went to Montana I wore the 9e in a shoulder holster under a short sleeve button shirt. The holster was one that encased the entire 9e except the grip.
I read several places that the gun can be bought NIB for under $300 versus around $400 for the SR series. Personally the raised loaded indicator never bothered me and I actually like it over the visual check on the 9e but to each his own. As usual IMO Ruger guns are best bang for the buck.
Here is a decent review of the 9e. http://www.ammoland.com/2015/03/ruger-9e-pistol-review/