I have owned multiple RMR optics for many years. Here is how I compare the RMR to the Acro.
While relative battery life is unknown, the Acro’s battery can be changed without removing the optic.
The Acro has a superior mounting system, clamping against a dovetail. The RMR and most other optics use screws which far too often are stripped. Right now I have a Shadow down because the base adapter plate is stripped. My first type 2 RMR failed almost immediately, and I stripped a screw trying to remove it. A T20 torx screw clamping against a dovetail is secure but still makes it easy to remove an optic.
A sealed emitter is a game changer for those of us around heavy rain and snow. The design of the Acro also prevents the lens from being a receptacle to collect dust, lint and other debris as is common with open emitter designs.
The RMR lens is tinted which is a negative. While it may be wider than an Acro, it is height that is most important to me for tracking a dot in recoil. In height, the way the Acro window is designed, the Acro visually appears to give you more height. Part of that might be the way BUIS interface with the Acro.
Reliability is still TBD but a safe bet would be on Aimpoint for durability.
Likes pretty much everything in every caliber.
On a pistol I really want a larger dot than a 3.5 MOA. For me a 6 MOA is minimum but I'd really prefer a 8 MOA.
I hope Trijicon has their new model there. I believe there will also be a new product from a company without a pistol optic currently. I hope the Shield W is out as well at NRA. Competition is a good thing, I believe pistol optics are here to stay, and a good product brings almost the price of a new pistol, so there is a big incentive for them to keep working on a better mousetrap.
Likes pretty much everything in every caliber.
All dots do that for me regardless (doc says I don't have an astigmatism but the results are the same) so turning it up turns it into a shooting star and makes it almost unusable for me. Larger dots do it less which is my other reason for wanting a larger dot here. I've given up on rifles entirely.
The misshaped dot has been a problem for me trying to shoot small groups with a carbine at 100-300 yards. On a pistol, at 50 yards and in, I don’t think dot shape matters, since you are shooting quickly and the dot is always in some degree of motion. If you are focusing on the dot, you should instead be looking at the target.
Likes pretty much everything in every caliber.