I just put an Trijicon RMR on an Smith & Wesson M&P Compact, using an FCD OPF-SW RMR plate.  The iron sights provided on the gun are way too short to be usable with that plate/sight combo.

I see FCD suggests a particular sight in the product description, but its a tritium sight, which I don't care for.  Also, I don't know if the uber high sights will fit into anyone's holster when I get one.

Are there any other options available for irons, or should I just resign myself to not having any irons effectively?

See if S&W will sell the suppressor height sights that are made for their 10mm and if they’ll work for your gun.


Or
https://www.trijicon.com/products/product-family/trijicon-suppressor-optic-height-sights-for-smith-wesson-pistols

Does you M&P have the "Standard height" factory sights?

Most folks run "Suppressor height" sights on RDS guns to provide a lower 1/3 - 1/4 irons sight picture.

A quality holster maker like T-Rex Arms & similar will offer holsters with Optic Cut + Suppressor height sights.

Bigger_Hammer

The pistol comes out of the box with "suppressor height" sights.  I think the problem is that they are set up to work with the thin plastic plates S&W provides us, not the much thicker and sturdier metal FCD plate. There is a substantial difference in thickness (S&W's plate is about .040" thick, versus the FCD one which is about .16 - its tricky to measure thickness when mounted on the pistol).   Close to 1/8" higher than factory suppressor height.

For sure there is a difference in sturdiness between the plastic plate and FCD's plate, but that comes at a cost of thickness.

I bought a 2.0 4&1/4" OR, PC .40 last year.  

Due to so many (read on the internet) complaints about the S&W adaptor plates I decided to try them on mine.  Zero issues up to now, with a Holosun green dot while shooting 180 grain FMJ and hollow points.  Even with the thicker plastic plate I've got no issues seeing/using the factory tall sights on the OR pistol with that Holosun attached.

Just in case, I also bought a DPP metal adaptor plate off Amazon.  I've used them on one Shield 9MM and that thin plate worked fine, so far.  Very thin.

https://www.amazon.com/gp/product/B0B7WQT6YV/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

Night Fision makes them, but they don't make a non-tritium model.

Ameriglo may have some in the works, the ones they have now are too low for sights mounted on our plates.

A set of all black Ameriglo suppressor height sights will do the job for cheap.