"The Scorpion EVO submachine gun will directly challenge the aging Mp-5s, and I think will easily unseat them."
Doubt it. If you own or have shot subguns like HK MP-5, HK UMP, Sterling, UZI, Swedish K, etc. you quickly realize that each has its very unique personality, pluses and minuses (and easily the worst of them, IMO, is the most "modern" design, HK UMP; it looks and handles like an ungainly and oversized slab of plastic; MP-5 is much more fun to shoot). Hopefully EVO won't be in that category, but it has to prove itself.
The HK UMP was intended to be a cheaper alternative to the MP5. I think some MP5s came in 10mm and .40 S&W, but proved to be unreliable in that weapon system. Hence, the introduction of the UMP after the larger caliber MP5 versions were withdrawn from the market.
Generally, the consensus on the MP5 is that it's easier to shoot and more accurate than the other sub weapons. However, it requires more regular cleaning and maintenance to keep it running. So ideal for law enforcement type roles, but not necessarily for a go to war/zombie apocalypse type weapon. In that role, the Uzi, Sterling, and Swedish K all are much better options...
Personally, I see the EVO's primary competition as the other modern polymer pistol carbines -- Keltec Sub2000, Beretta MX4 Storm, Taurus CT9 Carbine, Caracal CC10, various AR 9mms, etc.
Size and features, the EVO looks to have it's own market niche vs those weapons... But I look forward to seeing a detailed disassembly video to see the full extent of polymer. Keltec has several critical metal parts embedded in polymer receiver, Beretta has several critical parts like the hammer made out of polymer, etc.
Now, in the full auto LE configuration, time will tell, but a reliable, compact, and affordable sub gun could most definitely replace much of their current inventory...
CZ BREN rifles have apparently had some design and performance issues, with complaints from the Czech Army (and Czech taxpayers, since they are far more expensive than VZ-58), so lets hope that CZ has worked out all the bugs out of EVO, and it has no long term issues, like parts breaking.
To my knowledge the BREN still has issues and they will never fully go away... The BREN was intended to compete w/ the SCAR, ACR, etc, with multi caliber, quick swap barrels, and all the other military weapon acquisition by committee stuff that leads to utterly boondoggled weapons due to all the competing requirements.... See the F35 Joint Fighter program for a great case in point here.
There's a thread over on the VZ58 boards about a monolithic rail for the VZ58. At one time that was proposed as/for modernizing the existing weapon stocks. But for whatever reason, they rebuilt from scratch and the BREN won over the SCAR as the Czech Military's new weapon, really only due to it being made in the Czech Republic, while the SCAR wasn't...
But in brief, the Bren controversies are much the same as the M4 issues -- too much emphasis on accuracy/tight tolerances over reliability in the dusty/sandy conditions of Afghanistan that causes them to fail... The M4 obviously has a bunch of other issues at play too due to the DI gas system under sustained high rates of fire...
Unfortunately, the complaints with the BREN seem to mirror a lot of other CZ-UB declining quality observations by bigger experts than me... Unsure how much is nostalgia and how much fact but it does seem to be recurring theme...
But pistol carbines due to the relatively low pressures involved are generally very tolerant of abuse even if having some design issues/less than ideal material concessions to reduce cost of manufacture.
Look forward to folks, and hopefully myself at MSRP or less, getting hands on the EVO giving them a fair shake. I think they'll impress.
As a truck gun, I think these will be great. Wish the barrel was a little longer for home defense use (longer barrel means more blast/flash reduction). There are other tweaks too and the lack of metal reinforcements on the mags is another major complaint. And hopefully a pistol grip mod can be made available as well for a more vertical option...