Rost Martin RM1S Comp 9mm 3.6 in Black Optic-Ready
Pros & cons
What works
- Weighs 19.76 oz unloaded — nearly identical weight to a standard Glock 43X but with an integrated compensator.
- Integrated slide compensator reduces felt recoil and muzzle rise for approximately 25% faster follow-up shot splits in rapid fire.
- Optic-ready system accepts RMR-footprint red dots without requiring a $150-200 aftermarket milling service.
- Hammer-forged 3.6-inch barrel provides a consistent crown and improved longevity over standard button-rifled options.
Trade-offs
- Includes only one magazine — a second 10-round magazine adds $35-45 to the true cost of a functional carry setup.
- 5-pound Double Action Striker trigger has a noticeable rolling break that demands practice for precision shots beyond 15 yards.
- Nitrocarburized slide finish shows holster wear faster than more durable treatments like Cerakote or DLC.
- No iron sights included with the optic plate installed — requires co-witness suppressor-height sights for a complete backup system.
Video review
Expert review
Specs at a glance
About this product
The Rost Martin RM1S Comp 9mm 3.6 in Black Optic-Ready is a subcompact, striker-fired pistol engineered specifically for discreet, effective everyday carry by shooters who demand both concealment and performance from a micro-compact platform. It achieves this through an integrated slide-mounted compensator and optic-ready system, which combine to offer a significant advantage over traditional carry pistols in rapid follow-up shot potential. This package delivers on the practical shooter's request for a feature-rich platform in a footprint that doesn't require a wardrobe overhaul.
What is the Rost Martin RM1S Comp used for?
The RM1S Comp is designed for concealed carry where the shooter expects to possibly engage multiple targets or requires rapid, controlled follow-up shots. Its primary function is defensive, not competition, with the 3.6-inch hammer-forged barrel and integrated comp providing faster sight recovery than a standard micro-compact. The optic-ready system allows for modern red-dot acquisition, making it suitable for low-light scenarios where front sights can disappear.
How does the RM1S Comp compare to the Sig Sauer P365 XL Spectre Comp?
The RM1S Comp offers a simpler, single-source solution for comped micro-compact carry, while the P365 XL Spectre Comp provides superior modularity at a higher price point. The Sig platform wins for its vast FCU-based aftermarket ecosystem and proven track record, but the Rost Martin's integrated comp and 5-pound DAS trigger pull weight provide a more consistent out-of-the-box performance package for the shooter who doesn't intend to extensively modify their firearm. For those prioritizing customization, the Stevens 555 Sporting O/U model line showcases a different approach to aftermarket adaptability in the shotgun world.
What does it weigh and what are the dimensions?
The RM1S Comp is built around a 19.76-ounce unloaded weight with a flush-fit magazine, making it manageable for all-day carry without a heavy belt. Its compact footprint is defined by an overall length of 6.72 inches and a height of 4.4 inches, achieving a profile nearly identical to a standard Glock 43X but with the added benefit of a slide-mounted compensator to manage muzzle rise.
Who is this NOT for?
This pistol is not for the first-time shooter seeking the simplest possible platform, nor for the competitor looking for a dedicated USPSA Carry Optics division gun. The compensator introduces a unique maintenance and fouling profile, and the trigger, while consistent, demands a deliberate 5-pound press that some may find heavy for precision work. It's also a poor choice for anyone in a jurisdiction with strict regulations on ported or compensated barrels, as you should always check local laws.
What's in the box?
The factory box contains the pistol, one flush-fit magazine, a Trijicon RMR footprint optics mounting plate, a polymer hard case, a standard cable lock, and the owner's manual with warranty card. Unlike some competitors, it ships with only one magazine, so budget for at least one spare; this is a common but frustrating industry practice that adds $30-$40 to the true cost of ownership.
Is the RM1S Comp worth it at $466.99?
At $466.99, the RM1S Comp presents a strong value proposition for the shooter who wants an optics-ready, compensated micro-compact without paying for brand-name premiums or extensive aftermarket work. You're getting a complete compensated system ready for a red dot for less than the cost of buying a standard P365 and adding a third-party compensator and milling service. For the price-conscious buyer, exploring options like the Stevens 334 Rifle can reveal how different platforms allocate the same budget toward power versus portability.
Key attributes
| upc | 850067485636 |
| manufacturer | Rost Martin |
| manufacturer part number | RM1SBLKOSP10(COMP) |
| shipping weight | 3.0 |
Frequently asked questions
- Is it compatible with standard Glock 43X holsters?
- No, the RM1S Comp is not fully compatible with most Glock 43X holsters due to its integrated slide compensator and unique slide geometry. You will need a holster specifically molded for the RM1S or a universal model with an open muzzle end, like those from Vedder Holsters for the RM1 platform. Holster fitment time is critical, so confirm with the manufacturer before purchase.
- Does this work with Holosun 507K red dots?
- Yes, the included optics plate is milled for the Trijicon RMR footprint, and the Holosun 507K uses the same bolt pattern. Direct mounting should be possible without an adapter plate, but you will need to source the correct length mounting screws (typically M3x0.5mm, 6-8mm length) as they are not included with the optic. Torque to 15 in-lbs with thread locker.
- Can I return it if it doesn't fit my hand?
- Our policy does not allow returns for buyer's remorse, including hand-fit issues, on firearms due to federal regulations. All firearm sales are final once the transfer is initiated at your FFL. We strongly recommend handling the pistol at a local retailer first; our 30-day warranty only covers manufacturer defects, not ergonomic preference.
- How long does shipping take to an FFL?
- Processing typically takes 1-3 business days after order verification and payment clearance. Transit time via our standard carrier is an additional 3-7 business days to your chosen FFL dealer. You must contact your dealer in advance to confirm they accept shipments from online retailers and provide their current license. Delays can occur during NICS checks, which are outside our control.