I have one on my Beretta Storm and like it very much. I never played with the old Reflex so I can't directly compare but the brightness is supposed to be much better. It is still possible to wash out the reticle, but you have to try pretty hard. For example, indoors in complete darkness very close to a white wall with a powerful weapons light, it can happen. When I switched to this from an Eotech I also changed from a 200-something lumen (which is ridiculous for indoors anyway) back to the standard 60 lumen light and feel pretty good with that.
In all other conditions I've found the brightness of the dot to be very well adjusted--from super bright in sunlight to just the right level in dim conditions. This is one of the things I like best about it--I hated always having to mess with the Eotech to get it to the right brightness, which changes a lot whenever you're going anywhere (not to mention having to turn it on every time you use it).
There is a blue tint to the glass--it won't give you that "looking through an empty window" feeling the Eotech will--which might bother some people but it shouldn't really affect performance. It does give you that "looking through a big window FOV" that many like with the Eotech.
The reticle is sharp and well defined, not pixilated at all. Many will feel the dot size is a bit big for an AR-15 that one wants to use much over 200 yds, but for the 0-125 yds this carbine is capable of it does very well. Fist sized groups at 100 yds are easy, which is pretty good for 40S&W ammo.
I do think a well adjusted Eotech might be a bit faster and I did like the ring for help in holding on close range targets but I like the RX30's mount it, forget it, pick it up and start shooting simplicity better for this carbine.