The ACR is an excellent platform...however it is new which means it did and could still have some teething issues. This is to be expected. For examples, The XCR when it came out had massive trigger slap issues, slam firing problems, and a loose barrel bolts issue (Still has this) and out of spec barrels for that matter. The SCAR...hmmm...cost is the biggest disappointment and if cost isnt bad enough service and parts availability will put a huge damper on that! But the SCAR is in its 5 revision.
But before you write off the ACR remember it is extremely new and the price is coming down significantly...making it a more attractive platform. I have an ACR, the ergos and feel are second to none! It will be the most versatile platform out. The XCR was close but the stock is nowhere near the ACRs! And bushmaster remington have deep pockets not to mention friends in high places! The XCR has little to no aftermarket product that is exclusive designed for it. Both good in some ways and bad in others. But the bushmaster has a growing number of 3rd party vendor ready to make tons of goodies for it! It isnt perfect but it is the most innovative platform to date! It doesnt come without its complaints either, for me my main gripe is it is heavy. I dont like the grip (and you cant change it yet if ever) as much but the charging handle placement, bolt catch, mag release, stock, barrel design is amazing! It is more accurate then the XCR (at least when I had my XCR I wasnt impressed with its accuracy...it wasnt as good as a rack grade AR...the ACR is and actually doesnt climb as much as a rack AR. And good luck with RA support of the XCR...go to the forums, there is bitching beyond belief there! Not to mention Alex slow development and imaginary promises. I dealt with this first hand that is why I dont have an XCR anymore!
As for the SCAR, lots to love just not the price! Still 2600 is the cheapest I have seen! So with the enhanced ACR starting to get down to the 1800 mark this makes a wide margin of justification. But the scar has somethings I hate. The recip charging handle SUCKS! Why oh why...and its placement can be a little difficult as well with certain optics! The stock is alright but built significantly lesser to the ACRs. It just plain feels far more solid and versatile then the SCAR. I actually like the way the SCAR fits me better. The cheek rest fits me better. I also strongly prefer the sights on the SCAR..in fact I flat out love them! But really after that I am not running around wanting one...price is so steep...it it was under 2k...ok but To be honest I considered the scar but in my opinion it is not that dramatic of a change in a platform where as the ACR is. The ACR is far and away more versatile and innovative. I was on the fence as I said before about getting a SCAR but when I did some digging I would rather have a great piston AR like and LWRC or LMT. I like the SOPMOD and Vltor stocks better...the ability to fold isnt a big benefit to this recreational shooter so it becomes a non-issues and a novelty. I might use it one or to times like this and since I am not a soldier this is not a benefit for me. The SCAR is however very accurate. More then a rack grade AR and is also tested more dependable, I am not certain when you factor in the likes of LWRC for I am yet to see one viable bad post on them.
My only gripe is the weight on the ACR...oh and the sights...but that can be fixed with a different set. The MBUS to me is crap! I dont like them at all! Other then that it is a very nice platform! One that will offer far more then any before it!
Lets hear it! 
