When it comes to pistol-braced, PDW-style firearms, two of the undisputed names at the top are Maxim Defense, with its PDX, and Daniel Defense, with its DDM4 PDW. I’ve always loved these small PDW-style pistols and was lucky enough to get a couple of Certified Used selections out of the Guns.com Vault to review.

We’re going to pair the two up and let them battle it out to let you decide which is best for you.
 

HOW THEY ARE SIMILAR

• Both feature M-LOK on the handguards and come with included handstops
• Both feature ambi charging handles. Daniel Defense uses their proprietary Grip-N-Rip, while Maxim employs a Radian Raptor-LT
• Both feature ambi selector switches
• Both employ the Maxim Enhanced SCW Buffer system and the patented Maxim Defense CQB Pistol Brace
• Both pistols are available in .300 AAC. The PDX is also available in 5.56 NATO and 7.62x39mm, whereas .300 AAC is the only caliber for the DDM4 PDW  
• Both have flared magwells for easier magazine changes
• Both guns are also made in the USA!

I’m sure if you poke around the guns long enough, you’ll be able to find other similarities, but those are the major ones for me. Like I said earlier, these two guns have less in common than you might think, so let’s start with the major stuff. 

BIG DIFFERENCES, STARTING WITH SPECS

Before we dive into some of the smaller and more intricate differences, let’s take a look at how these two guns differ in terms of specs.

You may be scratching your head at the 20+1 capacity from the PDX. While it's true that the gun accepts all standard AR-magazines it only ships with a single 20-round magazine, so that has been listed as the standard capacity for the gun. It may be a knock for some people that the gun only ships with a single magazine, but at least its a steel mag.
 

The biggest difference in terms of comparison between these guns is obviously the caliber. I would have loved to get a PDX chambered in .300 AAC to make it more apples to apples, but it just wasn’t in the cards. That said, the .300 did produce more recoil, but I don’t think it was solely the caliber at play. The Hatebrake muzzle brake from Maxim does an incredible job of pushing gas downrange, but more on that in a minute.
 

Another big difference I noted about the guns right away was that the PDX has an adjustable gas block, whereas the DDM4 PDW is more of a standard low-profile gas block. While I didn’t do any adjustments to the PDX’s gas settings, Maxim recommends it only be done by a gunsmith, it’s nice to know the option is there for the guys who like to really fine-tune their stuff.
 

DIVING INTO DETAILS

There are some other smaller differences that are at play when comparing these two guns. Let’s start with the grip. This would probably be the biggest difference in terms of details for me. 

The PDX employs a CQG grip from Reptilia. It’s a fine grip and certainly more than capable of getting the job done. But when compared to the patented grip from Daniel Defense, it’s not even close. The grip on the DDM4 PDW is so comfortable, and these grips are something that Daniel Defense has become known for over the years, among other things. Besides the comfort factor, I also felt like it just stuck to the hand better. That soft-touch overmolding is almost stickier without being sticky somehow.
 

The triggers are also different on each gun. Some might argue that there is a big difference here, but both seemed fairly standard to me. That said, I’m not a regular AR shooter. I shoot enough of them every year, but I’d rather be on the pistol range. The PDX uses an Advanced Combat Trigger (ACT) from ALG Defense, which they put at a 6-pound trigger pull. I will say that I think the trigger pull is lighter and the break a little cleaner on the PDX. But for the average user, like myself, and given the intention of the gun, I don’t think it would make much of a difference in terms of putting hits on target under 25 yards. More on that in a minute.
 

The handstop is also different on each gun. Since my DDM4 PDW is Certified Used, someone swapped out the included handstop for a UTG angled foregrip. I have to say that I rather like this. Since you can readily find them for around $25, it seems like a great upgrade. I felt like I got a better grip at the front of the gun with the DDM4 PDW because of it. If I bought a PDX, I would certainly make this upgrade.
 

RANGE THOUGHTS

We took the guns out to 25 yards, put a red dot on top of each, and had no issues punching holes in the center mass of IPSC-style targets. I didn’t push past 25 yards or do any sort of accuracy testing because I don’t really see that as a use case for either gun. They are meant for close quarters. 

I put about 200-250 rounds through each of these guns, and I’m happy to report neither gun had a single malfunction – not that I was expecting one from either. The Maxim fed on a steady diet of 5.56 from Federal American Eagle and the DDM4 PDW ate up all the Barnaul I could throw its way. Both guns were a ton of fun to shoot. 

Both guns shot flat, but the PDX was especially low recoiling and stayed extremely flat due to the patented Hatebrake at the business end of the gun. This muzzle device is vented, and Maxim has found a way to use these vents to disperse a lot of the gas and concussion downrange. This makes for an incredibly flat-shooting firearm, which was especially evident when shooting rapidly.

I found this to be true not only when I was shooting the gun but when I visited Maxim Defense to tour their facility and saw shooters far more capable than me shooting. The Hatebrake simply works to dispel gas down range and keep you on target. While I can’t say if the same effects would stay true on the .300 AAC version, I can say this version was the flatter shooter of these two.
 

Of course, the spicier .300 AAC coming out of the DDM4 PDW was bound to create more oomph and muzzle rise during rapid shooting. That shouldn’t come as a surprise. Overall, though, the gun handled very well and still proved to be a ton of fun when just slinging lead.
 

CONCLUSION

Overall, I had a great time with both of these guns. If you’re looking for an AR pistol that is small and compact, these satisfy that need. Given the sterling reputation of each manufacturer, reliability should never be an issue as long as you take care of your gun. They are both a ton of fun to shoot at the range, so you can’t go wrong with either of these choices. 

If there is one stone to throw at them, it’s the price, with both of them commanding an MSRP of over $2,200. Of course, you might find some cheaper used, especially Certified Used, but they still won’t ever be cheap. Frankly, they shouldn’t be given the craftsmanship and attention to detail.

If I had to choose just one, I would choose the Maxim PDX because it’s chambered in the more affordable 5.56, which would probably lead me to shoot it more. Plus, I really enjoyed the way the Hatebrake performed. Both offer certain advantages though, and I wouldn’t mind having either in the collection.