I don't think it's fair to dismiss this question as to people liking to complain about everything, it is a legitimate question in my view, specially when the time comes to spend your money. The specs Linn published basically match what Audio-Techica had published for the AT-OC9XML since it hit the market. Now they are claiming modifications to the suspension while conveniently omitting compliance numbers. No manufacturer should be blindfully trusted, they should earn consumer's trust at every turn.
It is perfectly fair to dismiss complaints by people who have no idea of what they are talking about. Nobody who has complained has heard a Koil, nobody who has complained has any idea what changes Linn has made to the version of OC9 they based it on (and a compliance number is certainly not going to tell you anything particularly important music wise about changes to the suspension), certainly nobody who is complaining has heard the OC9 XML vs. the Koil.
Of course no manufacturer should be "blindfully" trusted. Neither should they be "blindfully" denigrated. When it comes down to it you make a choice based on what you hear. If you listen to the Koil and don't find enough improvement over the OC9, or you don't think the perfromance is worth the money, you don't have to buy it.
Is it a fair price? I have no idea. But neither do you. Lets try another example. The Krane is made for Linn by Clearaudio. It has some changes Linn specified including a Linn arm cable (which runs about $400 by itself). It is based on the Clearaucio Satisfy aluminum arm. In the US the Satisfy sells for $1700 and the Krane sells for $1755. Not much of a difference considering they are buying the product from Clearaudio so should be paying more than what it costs Clearaudio to make. So Linn didn't add an upcharge of 90% to the Krane - apparently they don't automatically do that, do they? Want another example? The Kendo seems closest to the EMT JSD 6 (at least based on the same superficial inspection people have done on the Koil - boron cantilever, fine line stylus). The Kendo runs £2800, the EMT £2680 (I couldn't find US prices for the EMT.). Yeah that's a really big jump!
Whenever Linn comes out with something new people are quick to claim they are overcharging for it. The Keel sparked a ton of such comments. The Arko is already getting such comments too when, again, nobody on these forums is likely to have gotten their hands on one yet. If you want to complain about prices why don't you try something real: eggs, milk, gasoline for instance? Those are some things where you know you are making a fair comparison as they actually
are the same things.