i tried it with progress springs. one rear ms3 strut blew in a month. they don't seem any better suited for handling or strut life than your oem shocks, nor did i notice that substantial of a difference in handling. in fact, i think oem speed 3 struts have even worse lowering characteristics given all the blown stock struts i hear about.
at the time i worked for the dealer and we just swapped my blown struts with new ones, so now the front is ms3 and the rear is mz3. there's no difference that i can tell.
save your money and pony up for konis, i wish i had.