I read dwindled in the context of emphasis below, emphasis mine:
I got my Bren with the purpose of it becoming my daily patrol rifle. I planned to use it for firearms instruction as well and letting my students use it. I also let my students shoot my scar 17. Why? Because in my opinion the reasons for owning an AR platform as your go to rifle have now dwindled.
[...]
So to me and most people I believe we will never give up our AR's, but you can't deny it is a dated platform and no longer the best of the best.
To be clear, I was only intending to share my perspective, and why it differs. Firearms are like most things -- be it trucks, dogs, women, politics, religion -- everyone has their own opinion and believe it to be right.
If not clear -- wanted to communicate that I don't agree that the AR is dated/archaic and cannot be made to compete w/ the "best of the best" -- recognizing that best of is typically subjective and dependent upon test design, not anything special between various weapon designs...
The original design of the AR15 is perhaps "dated," but the system and its variants continue to evolve. I would not classify the AR15 system where it stands now as dated or unable to compete. There are billet ambi lowers and ability to have full ambi controls on forged lowers w/ just a bit of dremeling for the bolt release to go to right... There are short stroke piston options, long stroke piston options, the CMMG mutant that takes AK mags and reliably fires 7.62x39, etc. There is so much diversity in the AR market that an "AR rifle" covers a tremendously broad scope of weapons.
I suppose I should add -- SBR DI ARs in 5.56/.223 w/ less than 11" barrels would be about my last choice for a rifle I'd intend to trust my life to. Now in piston configuration, you can go shorter and not have massive reductions in reliability -- but would still have the massive SBR increases in flash/blast and losses in ballistic capability of rounds fired.
In regards to the SCAR -- I believe there's a reason spec forces have pretty much dropped the SCAR-L in favor of updated M4 variants, and that reason reflects my arguments here. I believe the SCAR-H fills a separate use case.
Again, I'm defending the AR here begrudgingly...
Regardless of price, I thin the Bren gives the SCAR-L/16 a run for the money. W/ the Bren 805 coming in ~$1k less than the SCAR-L/16, I completely agree that it is much more value per dollar spent.
You seem to know a lot about both the SCAR and Bren. How do their barrels compare w/ anticipated longevity? Believe SCAR-L/16 has FN advertised barrel life of 20k rounds and the SCAR-H/17 of 30k rounds, but haven't seen Bren barrel life advertised.
And back to the OP's original question -- it's worth considering caliber as well for selection.
For me in carbine calibers, I prefer 7.62x39 over 5.56 in several respects, but here's a quick summary that might help.
-Indoor home defense: 5.56 (or 9mm pistol) carbine w/ 16" barrel for reduced blast and flash, shorter only if you have a suppressor w/ 5.56
-General purpose carbine for lazy/new shooters: 5.56 as it has light recoil and shoots flat
-General purpose carbine for active shooters (active meaning practice and familiar w/ bullet drop and trajectory) for outside of home use in urban areas (barrier penetration) and in wooded/brush areas (penetration and less deflection): 7.62x39 (prefer the VZ58 vs AK for 7.62x39 carbine)
-General purpose carbine for active shooters (active meaning practice and familiar w/ bullet drop and trajectory) for outside of home use in suburban areas: tossup between 7.62x39 and 5.56, generally longer sightlines than urban areas and construction quality has much less substantial cover of concrete/block/mature trees/etc
-General purpose carbine for active shooters (active meaning practice and familiar w/ bullet drop and trajectory) for prairies, crop farmland, etc, with longer sightlines but still limited by gentle rolling of land: 5.56
-General purpose carbine for long sight view terrain such as flat desert, sparsely wooded mountains at higher elevations or hills in more arid locations (in Appalachia or Ozarks for instance, I'd prefer 7.62x39 most of the time): .308
Note:5.56 does generally penetrate steel better than 7.62x39 where velocity, not mass is most critical... Otherwise, generally 7.62x39 has greater penetration.
7.62x39 you can swap in .300 blk or 6.8 spc, though both cost 2-3x as much per round with minimal add'l performance gains, IMO
7.62x39 is much more suitable for deer and hog hunting as well; I relegate 5.56 to coyotes and smaller
Thinking about big picture insofar as filling needs/roles, I tend to lean towards:
Pistol caliber carbine/SMG: CZ Evo, Colt 9mm, and Keltec 9mm Sub2k are all serviceable w/ different tradeoffs for each, like all of them
SBR: M92 pap or 11.5 in barreled AR (piston ideal here...) -- like these for vehicle, concealed/low(er) profile, and other such uses
General Purpose Carbine: 7.62x39 vz58/variant
Designated Marksman Rifle, or similar -- accurized carbine: 16" Mid-length AR15 Recce setup
Battle Rifle, or similar: traditionally this had to be a .30 caliber rifle, but I really prefer an 18-20" SPR type AR15 setup w/ rifle gas and a barrel tuned to heavy (75gr+) 5.56/.223 projectiles (especially take a look at capability to weight, etc)
Precision setup for self defense: a .308 AR15 M110, or similar setup
Precision setup for the range: a .308 bolt action
Precision setup for a 1000 yard rifle, actually any shooting beyond 750 yards or so: a .300 win mag bolt action
Combine the caliber preferences w/ platform options and you can see how you can really maximize effectiveness in multiple scenarios.
And add a .22lr and a shotgun or two of each (don't like shotguns for home/self-defense, but that's another convo), and you have pretty much all possible long arm defense and sporting needs covered w/ this selection.
Pistols are a separate discussion.
And similar weapons/capabilities can certainly be swapped for any of these, with some tradeoff in shared parts and manual of arms... I certainly have cool factor weapons not included in above and also have purchased weapons not on my ideal list while having yet to acquire all the above as well.
My philosophy (and justification to the mrs): make sure you fulfill the immediate pressing needs for your situation first and foremost (for needs, I'm more budget sensitive and focusing on maximizing performance and value) and then once covered, you can move onto your cool factor, collection, etc, stuff that is typically more expensive and/or less likely to be used. As you realize a known need has been met w/ cool factor weapon, then you can part with earlier acquisitions as you deem appropriate...
Again, on all, YMMV.
