Yup, have a momo fitted to the silverstone. Some fit better than others - ie some need Relays or pipes bending or moving. You should feel less flex in the front of the car on sharp turn-in. The down side is that you may understeer more easily on slow speed corners. They work extremely well with other suspension mods.
In short, for a few quid, get one.
FYI.. the guy in Japan is selling lower strut bars for most of the 155's - that's right, braces the bottom of the strut towers wink cool huh since that's where most of the flex is from.