OK, it’s time… so please advise…
Initially, it will mount on 16" Sabre carbine and a Colt 6520 until I get around to an SBR.
I like the PWS FSC556 and would like to add one… unless it will unduly restrict my suppressor options (Gemtech HALO).
So what options are the best bang for the buck, so to speak. 
Also, can a can designed for full-power 5.56mm be used an a .22LR rimfire, like a Ruger 10/22 or a .22 pistol and still be effective?
Thanks in advance… I’m working on my trust tonight.
Rmpl
I have the kac nt4 qd and I like it very much. I use it on my 10.5 lmt and 10.3 colt and with both you can shoot with no hearing protection; It sounds like a .22lr out of my ruger 10/22.
The best bang for the buck is by far the M4-1000.
YHM’s stainless 5.56 can is nice too. I would only recommend a fast attach can. I originally did not intend to buy a fast attach can, but now that I have it, I wouldn’t want to do without.
A handful of rimfire here and there won’t be bad for your 5.56 can. But if you plan on shooting a lot of rimfire, it’s recommended that you get a dedicated can. The filth of rimfire ammo isn’t something you want accumulating in your nice 5.56 can.
From what I’ve gathered, most people that are knowledgeable on the subject havesaidthat sound wise a suppressor from a quality manufacturer is going to sound(my wording/take on it) about the same. So other features become the deciding factor(s).
Price
Attachement Method
Durability
POA/POI shift
on those notes and strictly from my point of view
Price: the M41000 is probably the best value for a non-full auto shooter based solely on price
attachement menthod: my take - whatever floats your boat but I want a QD type when/if I move on a suppressor myself
Durability: the M41000 would be durable enough for me, but I am leaning toward the Surefire (see POA/POI)
POA/POI: Minimal shift is best. Considering that when/if I get a suppressor, I’d be using it on #1 SBR I’m in the process of trying to get (waiting form 1 approval) and #2 my Recce type 16". On the Recce, I knowI personally wont be too happy if I get so much shift that I cant hit clays at 150-200 yards with the suppressor on/off without adjusting my zero. The only suppressor I’ve read that I could expect that from is the Surefire or an Ops and of those I’d personally prefer the surefire.
Now all that being said. If anyone else has any advise for me (and Rmplstlskn) please advise! If I could expect that minimal POI shift out of an M4100 I’d probably be all over that. YMMV
POI/POA is indeed a high priority…
Rmpl
I have an SF 556K that is used on several hosts including an 18" Noveske, there is absolutely no change in POI with or without the supressor at either 100 or 825 (longest I shot it).
I have heard an AAC M42k, sounds about the same, weighs about the same, size is about the same, and if the list price is the street price for an M42k then they can be had for about the same money too.
Definately factor CS into the mix, definately read about CS, warranty work, and all issues related to rebuilds. I have used CS from SF before related to flashlights their response was “you broke it?, OK, we’ll send you a new one - free”. I bought the SF.
I think the best value for the physical asset is YHM.
POI shift has not been an issue for me. (M4-1000)
I get about a half a minute upward shift with the can on, and my groups tighten up by at least a half a minute.
As far as full-auto vs. semi auto… that’s a really iffy generalization to make. Like I always post… brainless semi auto fire can be more brutal to a silencer than controlled burst fire. The M4-1000 is plenty capable of full auto fire.
If you take ANY decent 5.56 silencer and slow fire a full mag, the can is going to be HOT!! Very HOT! You’ll be able to see the heat waves radiating off of it.
If money is no object, a Surefire or M4-2000 isn’t a bad way to go. The M4-2000 is supposed to be superior in materials to the Surefire cans, but I can’t remember the specifics. But the M4-1000 is really an adequate can for the vast majority of shooters.
I am researching .223 cans also (but will not be ready until Jan 2008:(). I have decided based off of info from M4carbine.net to go with the M4-1000. Not owning full auto weapons (or being able to feed one if I did) I think that this can is the best bang for my buck. It is not an entry level can, as far as features, but is priced like one. Given the political winds, this may be my one shot at one and I want it to be right.
Value buys: M4-1k or YHM SS Phantom without any reservation whatsoever.
Best of the best: Surefire 556k, Ops Inc 15th, AAC M4-2k.
I like the M4-1000 so much that I bought a second one. I had planned on getting an M4-2000, but the 08 version of the 1000 was so nice I just grabbed one of those. I got it at the 07 price too! 
I would not discount the Gemtech HALO - yes, it is older technology but it is truly a workhorse, general purpose cross-platform suppressor.
Any feedback on which dealer offers the best price & best service? Any M4C vendors?
Rmpl
Most of the time dealers are just selling for MSRP. I would find a stocking dealer over anything else. Even if I didn’t get my first choice in silencer, having a local dealer with a can you can put your hands on is the only way to start in my opinion.
E-mail or call Bryan & www.major-malfunction.com I had stellar customer service from him !!!
Buy from a stocking dealer. I would check with Grant, then down the list from there.
In Virginia, I would check with Harlan at Frederick Country Firearms if Grant does not have the one you want in stock. Or 3rd in line would be Polite Society Inc, then ADCO if you want an Ops or Gemtech.
A Form 3 between dealers adds a little time, but nothing like the 3+month backlog for a manufacturer to build a new one.
Yes. Support the dealers that ACTUALLY stock product. We’ve had these “jokers” in AZ over the years who can order you anything… No thanks, buddy.
I would suggest a OPS Inc. I realize that it does not have a “QD” function. However one must remember that nothing is QD when you have put rounds down the tube. We are currently seeing OPS 12th Models on SPR’s with a service life exceeding 50k. We have used OPS for MANY years and they always have performed outstanding with zero issues.
If you are gonna spend the money you might as well have one that will last.
Has there been any maintenance on that 50k ops can?
There must be a certain level of carbon accumulation with that many rounds through it!
Aside from operator level care and depot inspection, no. But you don’t see that coming out of many other mfg’s of cans (I will maintain decoum and not name any)
The thing I like about the Fast attach cans is that you can knock down some of the carbon build up in the blast chamber because you can get to it.
On the other hand, some folks just don’t bother at all. They only clean up when the mount gets so dirty it’s hard to install or remove the can.