Rpms are meaningless
The number of RPM's advertised my sound good, but the manufactorers should rate the machines for the amount of G-force its spin dry produces. The small tub of a twinny would have to spin a good deal faster to produce the same amount of force as larger tub going slower. I am no math wiz, but I remember some one once posted a link to a G-force calculator. Laundry Machines sold in the commercial/industrial realm are rated for G-force-Rpm is the rating used to bewilder the consumer market.