About 2 years ago the FTP Optics Alpha 3 (located here - you can save $15 with affiliate code "HUMBLE21" at checkout- yes it's an affiliate link but the following is unvarnished truth).
The Alpha 3 is a based on the C-More RTS2 footprint, which also shares a footprint with the Romeo 3 Max or Romeo 3 XL. It's a micro red dot with a considerably shorter and closer to the bore footprint than the old C-More Slide Rides. The body of the optic on the Alpha 3 is a little bit longer front to back - so your optic mount for Open gun applications will need to have a little bit more runway before the blast shield turns up - and a lot of optic companies are doing this already. If yours is a tight fit to an RTS2 - a Dremel and little patience can make them work - it's not much relief that's required.
The Alpha 3 comes in 6 or 8 MOA with a very limited run of 10 MOA dots. I previously have reviewed the 6 MOA dot in a slide ride application on a Glock 34 MOS with a C-More RTS 2 adapter plate. The dot did great for surviving two holster height drops with no breaking of the glass.
The window is very clear with no distortion. The dot is super bright - with the lowest setting being bright enough to be useable in outdoor sun - and possibly being too bright on overcast days for group shooting. The window itself is roughly Deltapoint Pro size, or RTS2 size but a tombstone rather than a round-ish shape. The adjustments are super positive but are accomplished via an allen key rather than a small flat head or large flat head (aka case rim) . The dot clarity is really great and the dot brightness can be made to bloom in a full midday Texas summer day. The downside to all that brightness is the dot will run through batteries pretty quick. So this is not a defensive use optic (it doesn't pretend to be) - this is used for sport and best used by turning off the dot between stages to conserve battery. Changing batteries isn't a big deal because there is a tray on there right side of the optic that allows for a quick change of a CR2032 battery.
So previously the 6 MOA dot I bought survived about 5k on the slide of my gun. I picked up an 8 MOA dot to experiment with larger dots and left it on top of my open gun for about 8,000 rounds.
The dot performed fine. Some solvent got on the housing and started taking off the logos - no big deal. I changed the battery prior to Nationals this year simply to be safe - but through only turning it on for practice and matches and turning it off between stages I don't think I had put too much of a dent into the battery.
The battery has a life of like 150 hours on a "match" setting - so that's a good bit of shooting before needing a swap. Ultimately I can recommend the Alpha 3 - it does what it's supposed to do at a price point that's more attractive than the RTS or the Romeo series of optics. Links included above are affiliate link - generating a small commission at no additional cost to you.