The RISCube Ultra uses a Pentium M processor which is usually found in laptops. A 1.7GHz Pentium M "performs roughly equivalent to a 3.4Ghz traditional chip", and reportedly gives the best RISC OS results R-Comp have seen.
R-Comp are likely to have this machine at the forthcoming SW-Show, and are asking visitors to order before the show for collection at the show.
Links:
RISCube
Press Release