The tire in the link is just an Ultremo tubie. It's not an 'R' model. In fact, Schwalbe has no plans to build an R.
From WW and a email that one member received from Schwalbe:
Dear Mr.,
at first we thank you for you´re intress in our products.
We seemed sorry to tell you that we dind´t are planning to build a Ultremo R tubular tire.
We ask for you´re understanding.
With best regards.
RALF BOHLE GMBH
Kundenservice - Vertriebsinnendienst
Manfred Greff