High spring rates can obviously degrade ride, my point was keep ride height stockish and with the right damping the higher rate springs will provide fantastic handling. With correctly calibrated damping, high rate springs are not that bad, try riding in a car with AST or Moton dampers and higher rate springs - magic. However, my point wasn't to go out and get 500 lb springs for a street ride, but if after a good auto-x or track day car, keep near factory ride height, and with stiffer springs and stock height car will be on rails.
VW/Audi does know a thing or two about suspensions, the tweaks they made to the TT prove it, unfortunately VW neutered the GTI with a roll center that needs to have the suspension sitting at stock height to maintain best grip, hence my advise to keep height near stock. They also wanted a certain amount of under steer in these cars as a safety net for the masses.
Koni Yellows with stock springs work great, running this combo now. There aren't issues with high or low speed compression damping, but it does require setting them soft on rebound for good street ride.
The reason you feel less jiggliness with DG springs is the fronts are softer than stock and the factory shocks actually control them a little better. Mk5 fronts are quite sensitive to spring rate changes. I just think the change from stock springs to DG to be subtle enough as to make the expense of swapping them at all debatable. For pure esthetics the early USA Mk5's with silly high factory height surely do benefit, the 08's and up are lowered from factory.
I have tested many different coilovers, companies providing them all have their own takes on rates and damping, I've no evidence they get things any more right, however many use (or have used) Koni's as the damper, so you tend to end up with something that works. Many coilovers on the market are junk, and the Farnorth articles correctly point that out. I used to sell KW as a retailer, they generally make excellent kits, the ST is great bang for buck setup. However the right set of springs on Bilstein or Koni dampers makes just as fine a suspension as any coilover setup, and I would say a better setup - install and forget. Coilovers are wasted on 99.9% of those who install them, and generally result in poorer max grip as the temptation to lower proves too much. Almost no one takes advantage of what coilovers offer - corner balancing, and for street cars its wasted effort. The typical coilover setup isn't compensating for the trashed roll center from lowering with stiff enough springs to keep the car from rolling even worse. If you want grip and lowering, you then need additional static camber and higher rate springs, or fix the roll center with H2sport or TT spindles. I had one of the few pairs of Mk5 spindles H2sport has ever made on my car, the improvement in grip was unreal, and tendency to lean greatly reduced.
Sways are less necessary for cars at near stock height with tall springs because the car still has its roll center intact. On a lowered car with a compromised roll center, additional roll control then becomes necessary to prevent more loss of dynamic camber - milder springs with sway bars generally ride better than a car with the spring rates required to keep it from wanting to roll more. When I had the sport spindles installed, even with up to a 50mm drop and modest springs, the car rolled very little. I would elevate sway bars to a higher level than "last resort", its a lot easier to adjust a bar than to change springs. Mk5's also highly benefit from both front and rear bars.
My ideal street setup is stock springs (or the DG's for a mild drop), Koni Yellows, and a pair of sway bars, and that's what I run now. Another nice improvement is knocking off some unsprung weight through lighter wheels, or converting front spindles and control arms to alloy.
