MaysEffect

The OP poised several questions, with the global discussion clearly stated on "what and why" makes a coilover setup good. None of the questions were focused directly on cost per quality compared to the OEM specifications. However it was asked, why and what made high quality kits worth the price. Throughout the previous answers and advisories, spring rates matched to the potential balance wasn't really discussed with any detail. As i stated before, most of the "blame" for what was bad or improper revolved around the dampers.

But in any case i don't see why buying a cheaper kit would warrant an argument of why its bad. That can easily be solved by the age old answer "you get what you pay for". The bigger question would be why a expensive coilover may perform poorly, and their are several cases like this. Who is to blame here? The user or the manufacture?

If we were to even make a basic calculation on even a reasonably spec'd coilover kit we would be over 1000 dollars at the very least.

Here is my breakdown.

Swift, Hyperco, Eibach have competitively priced linear springs at about $60-80. With an average cost of $70 per spring we already have a total of $280 for springs alone (basic spring kits are closely priced to this figure on average). Lets throw in a set of tender springs for good measure so that we can tune preload in fine detail. Tender/helper springs in most cases cost more than their linear spring counter parts because of relatively complex rates and design (flat coil, thinner wall). A average cost for a set will go for about 360 dollars ($90/per).

We are already at 640 dollars. This is typically half the cost for a basic coilover set, buying a coilover kit for anywhere around the price of the quoted springs alone means somewhere along the line parts, engineering or technician wages were significantly under funded. In any of these cases i hope cheap parts was the cause. An improperly trained technician assembling a product or a poorly engineered design of vital safety components for a car can be significantly more catastrophic of a failure than cheaper pieces IMO.

DAMPERS -
Given the increased complexity of any basic damper unit (considerably more parts/consumables per unit- oil, shims, piston(s), piston rod, bolts, seals,etc) We can already guesstimate a single damper would be more expensive than a spring. Internals alone for a basic monotube damper can be as much as 65 dollars (from actual price figures of a Bilstein monotube shock). This doesn't even include adjustable parts for a simple 1-way tunable damper like adjustable bypass valves, compression adjustment springs and so forth. in total a single 1-way damper can cost up to 120 dollars a piece, and if both front and rear dampers are of the same design, a set is about $480 alone.

Linear springs - 280
helper/tender springs - 360
Damper set (monotube 1-way) - 480
Total - 1120

This would be for dampers and springs alone. We haven't factored in assembly cost, accessory pieces and any potential R&D.

So in this case i would 100% agree that a cheap system COULD be worse than OEM.

On a completely different corner of this table i have a complete breakdown on the cost of a single Ohlins ILX 2-way damper and how it cost 940 dollars (no spring or external pieces). Without the discussion of springs based on the cars weight and potential load, this same damper system would ride equally horrible to a 666 dollar kit if not setup properly. So how or why exactly is the cost of the damper system a good bases of ride quality? Without springs they are just fancy umbrella's, and that was my point about how emphasis of dampers was the wrong primary priority.

Instead of bad mouthing companies and putting all the blame on them how about we figure out a bases for complaints? In reality, almost no one in history who took the time to write a piss poor review also took the time to measure the shocks performance in relation to spring setup, preload and other external factors.

In a notable case a few years ago, a clubracer bought one of the most expensive Moton kits on the market for a M3 e36. Without any practical testing and setup analysis the customer went on to completely slam Moton by saying it was absolutely horrible to drive. After having it sent out to a professional to have it "fixed", the technician found out the damper was set to FULL stiff (oil bypass completely closed) and a gas pressure over 150psi (not untypical or the source of problem for Moton's, but high). How long it was like this is unknown, but the customer gave zero notice to anyone before making these complaints. Was this the absolute fault of the damper? In almost all cases having a damper set to full stiff means you are compensating for a separate issue outside of the dampers control.

In a recent situation, a time attack team with a BMW 135i had a custom Nitron 2-way kit. A full review was made about the car setup (some may have read about this). Within this article the driver/mechanic lodged a small complaint that the kit was not working to their standards and was considering tossing it for something "better". Also within this review, pictures showed clear details of both the front and rear spring perches adjusted with well over 1 inch of spring droop when unloaded. There was NO PRELOAD on these springs, even with both F/R having helper springs on the setup. From this, we can discern the car would've been practically riding on bumpstops if this was truly how the car was setup in normal conditions. I have yet to here back from them for whatever reason after trying to ask about the issue.

Examples like this show where misleading statements can manifest improper analysis for anyone else looking to potentially work with companies.

Sorry for writing so much (not really ) rant over....