Now, the reason I say they are the best in the world is it uses pneumatic cylinders which means they don't lose pressure as the cheese compresses, spring types and other types do lose pressure. This is constant pressure which means you get a better, more consistent press.
Cartierusm, I don't doubt that these are very nice presses indeed. However, as someone who (among other things) works with mechanical, hydraulic, and pneumatic systems, I'm afraid I'm going to have to take issue with the statement above. Yes, spring presses are (IMHO) awful, not only because they lose pressure, but also because they are very difficult to calibrate for the desired amount of pressing force. Your press is vastly superior to a spring press.
However, "other types"? What other types are you thinking of? A dutch press, or any type of press that uses applied weight, either directly or mechanically multiplied, provides absolutely consistent pressure, with no loss and no gain over time - more consistent, in fact, than any pneumatic system can be.
<TL/DR warning on>
The precision and consistency of a pneumatic type of press depends on the precision and consistency of the regulation of the air pressure. You're not going to get either precision or consistency with a $75 air compressor, or even a $1000 air compressor. Let's take the latter: when you dial in, say, 10 psi on a high-quality air compressor regulator, you will be lucky if the actual psi stays within a +/- 2 range. Let's assume a 3" diameter pneumatic cylinder, which has a surface area of 7 square inches, rounded off. 10 psi would give you 70 lbs of force on the cheese (which then is spread back out over the surface area of the cheese, but that's another matter that applies to any type of press). But 8 psi only gives you 56 lbs, and 12 psi gives you 84 lbs - the latter being 150% of the former. 150% variation may or may not matter in making a given type of cheese, but it is not exactly consistent!
If it were simply that the regulator has a certain consistent error, that could be determined and compensated for. But in fact, the regulator will allow the pressure to vary up or down even during the time the press is in use. As the cheese compresses, the pressure in the cylinder falls, so the regulator must allow more compressed air in to compensate. And if there are any air leaks in the system - nearly impossible for there not to be at least a tiny bit of leakage - the regulator must adjust for the loss, even if the cheese has not compressed any. Each time the regulator adjusts, the result may wind up anywhere within that +/- 2 psi range.
In theory, the regulator on an air compressor adjusts for changes in the air pressure instantaneously and continuously. In practice ... not so much. The regulation is controlled by the pressure of a spring (yep, we're back to springs!) which is adjusted by screwing the control knob in or out. The pressure of the spring pushes against the pressure of the air being regulated - if the air pressure falls, the spring pushes the valve to allow more air in; if the air pressure is too high, the air pressure pushes the valve the other direction, allowing some air to escape. Between the spring and friction in the valve, this is not a system capable of precise and consistent regulation. Mind you, it does an excellent job of
coarse regulation, particularly for pressures of 50 psi or more. For a $75 air compressor designed for driving a nail gun and inflating tires, all you need is the ability to regulate to 90 psi, +/- 5. If you buy a $1000 air compressor instead of a $75 one, maybe you could even count on regulation within +/- 2 psi.
All this is not to say that pneumatic systems are bad, not at all. Where they shine is when higher pressing forces are needed, particularly if you size up the cylinder. For example, if you need, say, 1200 lbs of force to close up the rind on a 10" Cantal, you can achieve that with a 4" diameter cylinder and just under 100 psi - no heavy weights to move around, and even a +/- 5 psi variation is not going to matter much - that's only +/- 5% variation at 100 psi. This sort of higher pressure (100 psi is not really
high pressure!) with coarse regulation is where even a low cost air compressor can perform well.
But what if you need to start out with only 20 lbs of pressing force on a 6" Gouda to keep from prematurely closing the rind and trapping the whey? Here's where the pneumatic system requires a very different type of regulator - if you are still working with that same 4" cylinder that can give you the 1200 lbs, you would need to regulate to a very precise 1.6 psi to get only 20 lbs - not even possible to do with a standard air compressor regulator, so you're going to have to swap in a different regulator designed for low pressures, and you'd better hope it is better than +/- 0.5 psi in regulation, which means $$$. Even +/- 0.5 psi is going to be a +/- 31% variation at this low pressure! Or you could use a much smaller cylinder, say only 1" diameter; this would need around 25 psi to get the 20 lbs of pressing force - now +/- .5 psi is only +/- 2% variation, quite acceptable - so long as you have the expensive regulator. But now with the smaller cylinder, you have limited your upper end; a typical $75 compressor can achieve a maximum of around 100 deliverable psi (requiring around 135 psi in the tank), giving you only around 75 lbs of pressing force, which may not be near enough for the cheddar you wanted to make.
You could, of course, have a system with the ability to swap out different sizes of pneumatic cylinder, and/or different types of regulators ... but now we're getting a lot more complicated. And meanwhile, unless you spend really significant $$$ on the regulators, you're STILL going to get variations in the actual psi - maybe only a percent or two, but definitely not utterly consistent. Meanwhile, the dutch press IS utterly consistent, applying the same force, all the time, no matter what - and it costs $5 to build. Yes, it is bulkier, and it requires messing with weights (or hanging jugs of water). But it won't wake me up in the middle of the night when the air compressor has to cycle - have you heard how loud those $75 compressors are?
<TL/DR warning off>
Cartierusm, I'm really not trying to knock your press, not at all. It may well be that you ARE including a very high quality pressure regulator, and if so no doubt that is factored into the price. Nevertheless as the above TL/DR section demonstrates (should anyone be bored or daft enough to read it!) there is more than one reason to suggest that a pneumatic press is not necessarily the best in the world, particularly for a home cheese maker. Above all, there is every reason to contest the claim that a pneumatic press is the best in applying consistent force. Even with a very expensive, high-quality regulator, I'm afraid the pneumatic system is still going to be less consistent than a Sturdy Press, or a $5 Dutch press, or even, God forbid, the compound-lever frankenpress shown in my avatar.
