Been a Mirrolure surf chunker since the '60's, but I don't keep up with
nomenclature. I can't tell from your pic (no ring eyes) whether they are deep 52M, shallow 51M or floater 7M. Is the Series III "Jerk" a floater like the 7M?
or does this Series III refer to the color?
I use all 3, lots of different colors, and have had very good luck with the 7M floaters in this new finish in the 18 model (Black back, silver florentine sides) in clear, rough water surf in late summer, bays year round.
Haven't succumed to the urge to get into the 19M's and other new ones, but I have thrown the old 37M, as well as the 72M oversize and little 52's, whatever they are called.
They are all effective. Expect the rattles in the MR series to malfunction;
check them in the box before you buy.
Other than that, I stand by my slick signature.