I have kinda lost faith in kevlar lined tyres - it doesn't seem to me I have had less punctures with them in a great variety of tyres. Hard to call this reliably of course, there are no "with or without" tests from me. Even the mighty marathon Plus has flatted on me once. I don't think I have a particularly glass-strewn road to travel, I think it's just average.
Also, I haven't noticed any special fastness difference between the Plus and the Racer. Others don't have the same experience. Myself, I wonder about the magnitude of the effect in the overall scheme of things. I wish they'd publish numbers.