I really just can't understand the whole thing with adjustable cheek pieces.
A good for instance would be the McMillan stock on my spotters rifle. That stock - along with the work on it - was about $500 cheaper than a new XCR. It's got an adjustable cheek piece.
Now I've been using this spotters stick for 6 or 7 years - the barrel is about gone now again, and it's been with me through a basic and advanced sniper courses - so I pretty well know the stick.
The thing is, I'm CONTINUALLY tweeking the thumbscrew that secures the cheek piece. As in I'll twist on it probably two to four times per magazine just to make sure it's still tight. It's like a ritual, part of the doping process...... get the bipod level, check the turrets are zeroed, twist on the cheek piece thumbscrew, etc, etc, etc.
I for one have come to loathe adjustments like that. WHAT A PAIN! What's the other option? Well, you could do like the guys running the M24s, just duct tape a piece of pipe insulation on. Or I could loctite the thumbscrew in place - but if I did that I'd lose the iron sight usage capabilities. I could fabricate a spacer, to set between the top of the stock and the cheek piece, that would mean the cheek piece couldn't fall but then it'd require removal to go to irons.
And then there's the wiggle inherrent in any adjustable stock.
Sounds great for an expensive stock, right?
On a bolt gun, the answer is simple: lower the optics until it works. If the optics can't be lowered that much, adjust the comb higher without interfering with the bolt operation / removal. One, both, or a combination, will work every time in my experience. And when I say "adjust the comb higher", I'm talking in either a permanent or semi-permanent manner. Something that is SOLID, or at least solid enough. Bondo? Works great, but a touch heavy. The aforementioned pipe insulation and duct tape (the high-class way) works great too.
These changes work because a bolt gun uses one plane for sighting - unless going to iron sights, which one doesn't do anyway 'cause the Redfield sights just suck. And, of course, this is assuming that the stick is set up for irons. Me personally? I wouldn't trust the irons if the stick took such a hit as to screw up my optics.
But the thing is, the XCR uses ONE plane for sighting, whether it's optics or irons. Thus, in my opinion, the comb height should be adjusted to fit the user, and left there permanently. It's not like we're messing with the last eighth inch - I don't change the cheek piece elevation when wearing a baliclava or such. Just get the stock height right for that person, and then the factory tubular stock is a wonderful thing.
The benefit to the tubular stock is that it's got a slim footprint! That's part of the reason I hate the M4 telestocks - they're wide enough in footprint such that using them as a rifle (as opposed to a carbine) is problematic. Maybe my shoulder just doesn't have a big pocket, I dunno - but I don't like having to tilt my head to the side in order to get on the optics.
If I could have gotten the tubular stock higher, I'd have stayed with it completely. The only other possible gripe with the tubular stock is the lack of a storage compartment, but to that I give a resounding "who cares". The benefits? It's LIGHT, and since it's impossible to get a round stuck above the carrier on the XCR, durability of the stock isn't so much a concern.
Literally, it seems to me that the M4 adaptor could be manufactured in a low-medium-high selection. Put a half inch between each one, and call it good. Or call it "the best".