If you had to choose between the RX30 and 517/557 which would you choose and why? Thx!..
Tomac
Well, you know y answer already - since itw as you who let me borrow your RX30 to decide between it and an EOtech.
The idea of being battery free without spending TONs of money was very appealing. However, I was a bit disappointed of the washout factor on the RX30 just when walking thru my home with it mounted on my MAR. Even with all my lamps on, I lost the dot from washout 2-3 times.
Also - searching for the dot took me longer - as I am used to the eotech reticle I already have on my PS90. This is an issue not specific to the RX30, however. The dot size is similar to an Aimpoint, or any other red dot scope. I find the larger circle of the Eotech reticle much faster to pick up. Plus, if you know how to make use of it, you can use different points of the reticle to aim with at distances that differ from your zero point (I know that with my 50 yard zero - I can use the very bottom tip of the reticle for up close distances in the space of my home).
I really wanted to go with the RX30, but couldn’t make myself like the design enough to buy one. I nearly went with a 512 or 517 model eotech, but opted for the new XPS-0 model.
I never had a battery contact issue on the 511 I had, but I didn’t want to chance it. The XPS model has the battery in sideways - and the battery life is a lot more than the 511 model. After I got one, I decided to buy another for my PS90, and I sold the 511 model I already had. Now, I just need to worry about 1 type of battery for both.
But even if you want the longer AA battery life models, the Eotech is a better sight than the RX30, IMHO.
Only improvement that I wish eotech would make is a manual control knob for brightness, instead of having to push buttons multiple times.
I am happy to see that when I turn my XPS models on, the default brightness is higher than it was when I turned on my 511 model. I always had to mess with the setting as soon as I turned the 511 on. With the XPS, I can turn it on and go, if need be.
RX30. LOVED my EOTech, but the red dot started getting a corona, and the BDC dots on my 557 were ‘dancing’ on me, due to my Astigmatism.
I was a bit skeptical of the amber dot in bright sunshine, but I’ve gone from shade to BRIGHT summer sunshine with mine run it in the winter with the low winter sun, and I can STILL find it (and the bullseye!) every time - with NO corona! 
As an alternative to the red dot, I can highly recoomend the RX30. In fact, I’m looking for ANOTHER, for my current build!
The EOTech reticle is way more useful in the field than a 6.5moa dot. IMO,“No batteries” is of vey little significance compared to the utility of the reticle. You should be able to do as good with irons with practice as a 6.5moa dot…
I would suggest the RX06 which has the triangle so you have the tip for a finer aiming point. Plus you have the Polarization filter which takes care of the washout problem.