M1 vs M2 vs M3 what is the different.

M uses the 18MP 650D sensor

M2 uses the 18MP 700D/100D sensor

M3 uses the 24MP 750D/760D sensor

M and M2 sensor have nearly identical noise performance, but the M2 version has more on sensor AF points spread over a larger area.

M3 sensor has about a 1/3 to 2/3 of a stop advantage (at high ISOs) in noise performance over the M/M2 sensors.  M3 sensor also adds even more AF points over an area similar to M2.

Overall, all three cameras have good sensors and all are capable of producing very high quality images.

M and M2 have very similar bodies with near identical controls and construction.  The M2 is slightly smaller, has faster AF, much faster shot to shot time, and WiFi for remote shooting and image transfer.

Compared to the other two, the M3 adds a built in flash, ability to add a clip on hot shoe EFV, tilting touchscreen, faster AF with EF-M lenses, and NFC to the WiFi.

Aside from price, there is no reason to choose an M over the M2.  The M2 is either the same, or better than the M in all regards.

Choosing between an M2 vs M3 is trickier and will depend on your friends needs.  Using the EF-M 22mm lens, the M3 will focus a little faster and produce images with a little more detail and a little less noise.  However, the M2 is noticeably smaller and significantly cheaper.

If your friend wants a pocketable, high performance package, they should get the M2.  There is nothing smaller available from any manufacturer that can match the performance levels of the M2 and EF-M 22mm f2.0.  If your friend would prefer a "mini" DSLR experience, then the M3 is a better choice with the larger sculpted body and potential to add an EVF.

One other small consideration.  The M, M2, and 100D all use the same battery (LP-E12).  Spare third party batteries are readily available for next to nothing.  The M3 uses the same battery as the 750D and 760D (LP-E17).  Currently, there are no third party options for the M3 battery and original Canon units cost 10X more than the aftermarket M2 batteries.

thedanj wrote:

I don't have much to add to what others have said except to say that I've owned all three, and now I shoot with the M2. I was pleased to discover that it actually focuses faster than my M3 did in most instances, and I vastly prefer its color rendering.

I too have owned all three, but now shoot with the M2.  If I was to make a VERY broad generalization about AF speed it would be this.  With EF-M lenses, the M3 is probably faster in more circumstances.  With adapted EF lenses, the M2 is probably faster in more circumstances.

Photato wrote:

Great summary nnowak.

I would add that only the M can run Magic Lantern which gives you additional features.

Also only the M and M2 can do Video at 3X lossless magnification which is an essential for wildlife shooting.

The OP question is loaded and to properly answer it would require a Table of more than 100 items

I forgot about the really cool 3X video zoom, which I only just recently learned about.

Correct me if I am wrong, but isn't the 3X video zoom only available on the M via magic lantern whereas is is native on the M2?

nnowak wrote:

.....

M and M2 sensor have nearly identical noise performance, but the M2 version has more on sensor AF points spread over a larger area.

a small correction:

Same # of AF points-31 (M/M2), but maybe a larger area of sensor-not stated-but not significant as we mostly use the center AF pt don't we?

The AF sensitivity is the same for M/M2 as well- EV 1-18.

The M3 has 49 AF pts, but the sensitivity is LESS, EV 2-18 !

GL to OP's friend!

I found there to be one important feature that is included on the M1 and M2, but removed on all subsequent models. This is, the ability to recognize independent left and right input channels through a stereo 3.5 inch” cable. 
If you happen to have a Tentacle Sync E timecode generator, you can quickly see what I mean. Plug TS into the M1 Or M2 and the Left channel will be the audio timecode and the right will be the mic which is on the TS. Completely independent of each other, with no cross bleeding. From the M3 forward the inputs are combined. If anyone has found a workaround or magic cable or adapter to bring back discreet Left and Right input channels, please reply with any info. Thank you for reading, happy new year!