Posts on the previous thread indicated that the diaphram used in the MCA SP1's are the same as the MXL 1006, a 25mm diaphram. But from what I read on rec.audio.pro, the capsule is the same as the one used in the MXL 603, a 20mm diaphram mic. This raised a question as to whether the SP1's should actually be considered a true Large Diaphram mic, but I'm sure JW at Audio Upgrades could let you know for sure.
I would be very interested in hear how a set of the SP1's sound.