Actually, the Decca arm is slightly heavier than the Rega, so there will be no mismatching problem in this sense. Also, if you find the bass woolly, then try out the damping, adding thicker oil to deal with woolly bass, and thinner oil to deal with over-damped bass. Tiny as the cup is, the damping on this arm really works! Finally, the Decca sounds great with all MMs I've tried out so far, being an incredibly musical tonearm. Good luck in your Lenco project, the end result will floor you, as it does even those with top-of-the-line no-holds-barred high-end rigs. How can the Garrott/Decca not sound stunning in such a rig ;-)?