Here's a review from one of my buds on HKPRO. Enjoy,
I recently put my hands on a brand new Mr223 A3, it's a factory 11" RAL8000 version with modified muzzle device to accept a rotex Suppressor.
Needless to say (on this forum at least), this is the closest you can come to the HK416A5. As a consequence, the expectation bar was and is understandably high.
Benchmark: I have shot and own a selection of competing .223 SBRs such as Mk18-like AR's, SCAR-L 10.5", SIG553 and G36C
First feeling & Ergonomics: 4.5/5
Out of the box the gun feels solid as a rock. It is right on the top of the league with the SIG553. Upper and lower sit together really tight. The A3, near the rear take down pin has some sort of device which puts tension on the take down pin. There is no rattle whatsoever (not sure if I'm describing it in technical sound terms, but the effect is this). The slimline stock is really flat on the cheek, but then again it's not called slimline for no reason I guess. Stock pistol grip sucks, I don't like the angle (this eats away 0.5 out of the overall rating) - I replaced it with a spare Ergo I had. The safety switch has a very positive feel to it - light years better than the G36C one. The iron sights that finally come out of the box, are really nice and actually as useful as they look. The new handguard looks awesome and has a solid feel to it.
Manipulations 5/5
Manipulations on an AR are high speed, the A5 imporves a bit on the traditional Ar15 in these ways: Enhanced CH (better angle); larger bolt hold open paddle (bigger, more surface and good texturing). For lefties there is a little lever to release the bold also on the right side of the rifle. Same goes for the mag release. Note that these little adjustments are not a gigantic leap in technology BUT finally HK puts it all together in 1 package and they all fit well together. No need to go aftermarket (finally). Trigger guard has also been enhanced, although I never had an issue with the old (flat) one. At the range working around the platform is pleasant, all the parts work well. the trigger is crisp and the pull is smoother than my other ARs or SCAR. Not gritty but also not comparable to the SIG which is still superior IMO. You can shoot fast mag dumps but still achieve good accuracy
Accuracy 5/5
I shot with iron sights only at 100m, and the accuracy is outstanding. I have 3 reasons in mind why that is so. 1) Iron sights do their job extremely well. I feel very comfortable with them, they're as solid as BUIS can get (unlike the SCAR) and are fully adjustable in an intuitive way. They are superior to the KAC Taupe I have on the Mk18 - and that one was already pretty good. 2) The trigger is smooth enough so that from day 1 you can pull off some nice shots without having to find "the spot". 3) the barrel is heavy as f**k and 11" long. Among my SBRs with iron sights, the MR is the highest scoring platform. The SCAR and the Mk18s come second, the SIG553 third and the G36C is the worse of all (borderline useless with the stock iron sights made of plastic btw). The SIG551 scores better with stock iron sights, but it is almost full length so not really an SBR for me. Adding the suppressor did not change the POI a noticeably, here is where the ultra heavy barrel comes in handy I believe.
Agility 5/5
The rock solid feeling and heavy accurate barrel come at a price, especially if working with a suppressor. With irons and suppressed, the gun was a liiiittle nose heavy. Comparable to the SIG553 though - which left me positively surprised given that the MR is longer. I am curious to see how it performs at 300m, eventually if performance is consistent one may really wonder if a 14.5 or 16" platform is justified. Granted i'm more of a short range mad max, for me anything beyond 300m is unappealing. Anyway the nose-heavyness can be easily offset by some push ups each morning. No deduction in points for the excess of weight given the positive impact on accuracy.
tacticool 5/5
This gun is AWESOME. For ages I was not sure if to SBR a random MR223 or not. Thank God, and also thanks to Baljar and Montrala I did not. They said that HK eventually could and would bring an SBr to market as the respective German authority approved it back then. Well the gamble paid off big time! The package is as sweet as it can get. With the exception of the muzzle device and pistol grip, we get all of the HK416 A5 furniture. including iron sights which on the market are priced well over 200€. Add the RAL8000 magic and it does not get any more tacticool than that. I feel kind of sorry for those who already own an SBRed Mr223.. A somewhat expensive operation for a package that is now available out of the box for a surprisingly competitive price (for HK standards). The only thing missing is the adjustable gas block. But I ran the gun suppressed without any noticeable difference. I wanna torture this thing to see if HK really does things right.
price point 4.5/5
I managed to grab one for a price that is 70% of what a new SIG553 would cost me. it is around 35% more expensive than the average AR15. In the price range, I would say that the MR223 is for once not the "usual" HK ripoff. The Haenel in 223 offers the same technology for less price, but not a lot less. I'd say the Mr223 is the best AR15 platform money can get you across Switzerland. You can plink .223 for less money, but the collector's value and historical background of the MR223 would be missing.
overall rating (not an average) 5/5
As far as civilian legal HK rifles are concerned, this is an amazing package for a competitive price. We could rant about the missing adj. gas block, but then again years ago we would have spent hundreds of extra $$$ on top of an inflated base price just to cut the barrel! If you can or where thinking about grabbing one, don't hesitate to pull the trigger! Will try to do some more testing with more pictures these days. If you wish to see some specific parts, let me know!