I bought this cylinder head with the specific reason to < possibly > aid in feeding issues I have had. I figured the additional few hundred microns might be able to assist in a slightly longer tappet/nozzle open window without using a delayer ( it didn't work as I hoped ).
Other design decisions at first glance also made sense to me. The Teflon PTFE coating, "extra fit" stem, the securing screws, are all good, additional features. Besides the enhanced tappet travel feature, I was also excited to try the extra fit stem too.
That being said, this is an expensive cylinder head. Obviously, you can see the price tag yourself ( $33 at time of review ). I have used this in three replicas so far, and while this cylinder head did not fix my feeding issue, that was not what the manufacturer or product description went along to claim anyway.
How does it perform as a cylinder head?
Exactly as expected. Nozzle stem was the right length for the ballpark of ~21.4mm, and it generally seals well with most nozzles I have used ( Orga firefly still leaked until I changed the seal ). The fit is noticeably tighter to be sure, but of course with lubrication the extra friction, if any, is negligible and should not affect performance in my opinion.
Surface finish is also fine. I cannot verify or deny any of their claims in this regard. Time will tell if it holds up better than traditional anodizing.
In my own, limited to 3 installations so far experience; I noticed the mounting holes are a pretty precise, tight fit. This is a good thing with a double edge, as I had one instance where the fit was too tight and I could not seat it in the shell, but this is not a unique issue. If I remember right, SHS cylinder heads are also historically pretty tight... But it's been years since I've used one because they're always out of stock......
In order to address that, I very slightly opened up the holes with an SAE drill size that I just reached for. I don't remember what it was, but being SAE, you can trial and error your own collection. All I would recommend is put a nozzle, sacrificial or otherwise to protect the stem for any slip ups you might have.
The incompatible gearbox was an APS/EMG Silver Edge gearbox ( don't @ me, these gearboxes are perfectly fine )
Airlabs Cradle, and Retro Arms fit just fine with no modification.
I opted to not use the set screws to "lock" the cylinder head in place. The fit is precise enough it doesn't move anyway, seating with a pretty satisfying snap. I figured the "tuning" step would just be unnecessarily annoying and provide negligible benefit if any. Not worth my time, especially waiting for threadlocker to cure. But, I expect I will need them for my modified cylinder head if I decide to move it to a different gearbox. So don't throw those away.
Would I buy this again?
I don't think so, personally. In my opinion, with cheaper alternatives in mind, this cylinder doesn't solve any real problems ( again, opinion ), and the enhanced tappet travel is really a min/max mindset. This is a very premium price, compared perfectly adequate cylinder heads can be had for $8, or, extra fit version from Brill proper for $18. That is almost double the price, for what appears to be no extra benefit compared to the next competitor.
So who is this cylinder head for? Someone who REALLY needs it. Again, a min/max. If you need the best of the best, with adjustability and tightest performance and no budget this might be might be what you want. But if you are just some guy who repairs AEG's from time to time. I'd save your dollar for a similar product.
disclaimer, I have not used shop brand Brill cylinder head yet so do your own diligence.
Otherwise, I have never personally had a cylinder head with a non-intentionally loose fit ( Lonex with damping pad and oven mounting holes, allowing for "shock reducing movement" causing feeding issues ). The cylinder heads either fit perfectly, or they didn't. The ones that didn't had a similar just bore it out a little bit and it will fit issue too, so ultimately, all of my cylinder heads across stock brands, stock CNC, aftermarket CNC like Retro, SHS, and Lonex all just fit perfectly.
Similarly many 10's thousands of players have achieved consistent, long range, high RPS performance without technology like this,using appropriately sized nozzle already compatible with their replicas. +/- 1FPS shot consistency has always been long achievable without innovations such as this.
Does that mean you shouldn't buy it? No! In fact, if you have some extra dollars in your wallet and you want to SUPPORT a company that is currently innovating, then by all means, this cylinder head WILL work like a cylinder head. Support your innovators! But, if your budget is tight, or, like in my experience, the damping pad you want isn't in stock; a different cylinder head will most certainly work just fine.
But remember: this is airsoft. Your milea...
