True... they are virtually identical except for a few features in the amps, and the obvious difference in that the RK II also uses EL-34 tubes.
Read our in-depth review of the RK II, which goes into full details of the differences between the RK I, RK II, and Roadster.
http://www.musicplayers.com/reviews/guitars/2006/0906_MesaBoogieRoadKing.php
Scott