I agree with not using SPM and Quattro together. Use all of either one, preferably the Quattro. If you did not guess from my earlier post, I think the Quattro are worth the extra cash over the SPM.
I recently have developed a liking for the Blue Circle BC95 which lists for only $250 for a meter pair. The BC95 is not the best at anything, but accross the entire frequency spectrum it simply "sounds right" to me.