I've been slowly restoring my 2 poor man's SP10. Technics SL1200 mk1 actually have the same motor as the original SP10 and SL1000.
The original part numbers for the different motors vary.
SL-1200/SL1100 MJL-9A (or MJL12A for some SL1100)
SP-10 MKI MPL-10A
SP-10 MK2 SFMZ102-01E
SP-10 MK3 SFOP109M11A
SP-15 SFMZ015-02Z
SP-25, SL-1200 Mk2-5 SFMG520-31A
That does not mean the motors from the original SP10/1100/1200 were internally different, just different part numbers. You'd have to take the housing off to tell, and I don't know. It certainly would not surprise me if they were the same.
Stereo Review reported an SL1100 showed the better specs than the original SP-10, but that could have been unit to unit variation. Certainly the original SP10 was no better than the SL1100-1200, motor-wise.
SP-25 and many of the SL Mk2 series turntables shared the same motor. I haven't checked, but I would imagine that the SP-15 shared the same motor and similar electronics as some of the later SL series that featured the digital speed readout. The SP-15 offered 78 rpm, though. There were also some mostly Japan-centric models such as the SP-12 and SP-20. And of course the top tier Mk3, last of the 'old' line.