Everyone referring to (especially Ron) Sikaflex 227.

My concern is that its gonna be too soft, because I have heard people use 227 for the windscreen sealant?? being used in that sort of application would mean that its quite soft??? I wouldn't really know. Can anyone confirm this.

I bought a tube of 227 ready to fill in my mounts very, very soon.
Should I exchange it for a tube of 255???

My application is just spirited street driving.
Thanks