The Sachs suspension is the stand out feature of the Trophy model.
The whole damper unit is of a higher standard than is normally found on a car in this price range.
The damper shaft is much thicker than a normal damper rod, this means there is much less flexing of the shaft meaning a more controlled placement of the wheel under heavy breaking and cornering. The shaft is exactly the same unit as used on Jason Plato's and Darren Turner's 2008 Seat Leon TDi BTTC cars, as are a few other components used in the Trophy damper.
Of course to accommodate a thicker shaft you need a remote reservoir for the gas as there is not enough space for it, as with all dampers the gas is pressurised to prevent cavitation of the oil in the damper unit itself. The only other system I have seen for the Clio with remote reservoirs is the AST stuff, but then it is geared towards competition/track work, therefore other system must have a thinner shaft.
Although Renault fixed the damping rate, you can "unpin" the adjuster on the remote reservoir making the front dampers adjustable in compression, from softer than Renault set to harder, though the overall damping is firm but controlled, & believe it or not firmer than some BTTC cars are set at.
The units are also like competition units rebuildable, which is much cheaper than the I believe £1200 or so Renault charge per damper, but they do need maintenance.
Most aftermarket suspension system prices are reflected in there Research and Development costs, a set of "coil-overs" at £500 has to be questioned not only in research and development, but also in the quality of manufacturing processes and material's. Although with a car like the Clio where a manufacturer can bank on a higher number of units being sold can then sell cheaper than maybe more specialist cars.
My integrale for instance has two stand out systems, ohlins at £2600+ or Ron Simmons (RSR) of the 75 Experience at Nurburgring fame who designed and developed his own integrale system which costs some £2000+, even the FK Automotive systems at £800 and KW at £1000 are no where near as good, but part of those costs are reflected in a much smaller marketplace for the products to make a profit in.
Many aftermarket systems geared towards primarily road use are over sprung and underdampered as the marketing men make the final decisions because the end user will not accept that a system that is not very firmly sprung, even if actually against the clock the softer sprung harder faster reacting damper is faster.
And of course you have to price the systems towards the demographic of the end used, there is no doubt not many Clio owners are going to buy £2K+ of suspension systems for cars in many cases are not worth much more, so again economics come into what the end product will be like.
I'm not saying you can't get better than the Sachs set up, but the development engineers spent a lot time getting the set up as good as they did, and you would have to go a long way to bettering it for its all round ability.
