As Michael 3.0 was created from the same Unimesh that Victoria 3.0 was made from, there is a strong compatibility between the two figures. In fact, all the textures maps that have been created for use on Victoria 3.0 should work fine on Michael 3.0. However, not all textures created specifically for Michael 3.0 will work 100% on Victoria 3.0, due to several modifications made to Michael 3.0 during his production.Texture maps made specifically for use on Michael 1 or Michael 2 will not work on Michael 3.0.
There is a method to make them work, however. The "Universal Texture Converter" that is for sale in the DAZ3D online store, will convert your Michael 2.0 maps to work with Michael 3.0's new UV setup. There are also several texture maps that were created prior to Michael 3.0 (for example, the V3 Male Morph Pak contains several male texture maps made specifically for Victoria 3.0 and are compatible with Michael 3.0) that work well on Michael 3.0 as well. The one limitation being that the genitalia on Michael 3.0 is original and there were no existing textures for that particular portion of the Michael product prior to its release.
Universal Texture Converter: http://www.daz3d.com/i/3d-models/-/universal-texture-convert?item=1212&_m=d
Universal Texture Converter for M3: http://www.daz3d.com/i/3d-models/0/utc-michael-3?item=1556&cat=&_m=d