I had a chance to install these on my car last weekend, and I'm exceedingly pleased with them! They are completely silent, did not add any perceptible NHV, and being sealed from the bottom should keep the monoball operating freely (and silently) for a long time to come.
Here's excited for them...
Traditionally there's two types of RSMs: Bushing based or monoball based. Both have tradeoffs.
Bushing based RSMs must to be soft enough the angle of the shock to change, at various points on the suspensions travel (so that the shock doesn't bind, and/or ruin its seals-- more important on higher end shocks, but always useful). This solution meant low NHV, but the precision with which the shock could control the wheel was significantly restricted by the need for fairly soft bushings. Most of my cars life has been on these.
Traditional monoball based RSMs allow complete shock articulation and 100% precision, but transferred NHV is very significant (annoying). Over time, the monoballs themselves can get noisy as they are not sealed from dirt. Good for race cars, not great for street cars or street driven track cars. I ran these for ~10,000 miles before I got fed up with them.
ECS's new Polyurethane-isolated monoball RSMs are very much the best of both worlds. They have a bushing, but that bushing is only responsible for NHV control-- the monoball is there to allow to shock to articulate. That means they can use a much stiffer bushings, allowing the shock to be much more precise in its wheel control. They also include a gasket to seal the bearing from below, which should keep the monoball operating as new for a much longer time than traditional, unsealed monoball RSMs.
The result is just kick ass. Almost all of the precision of a full monoball RSMs, no perceptible increase in NHV. It's the perfect RSM for anything other than a dedicated race car, IMO!
Some pictures from ECS's site, because I didn't remember to take any:
I'm super pleased with them
