As prices become more affordable I've been interested in leaning more about full frame.

a) IQ

When I compare the Kodak Color charts in the 7D I'm taken back by how much better the 5D2 image quality is than the 7D +1/3 S=2 crops. The difference in resolution is astounding. The full frame ISO looks at least 1 stop better as well.

b) DOF

I came across one of Daniel Browning's posts on another forum and this is what he said:

100mm f/4 on APS-C has the same angle of view as 160mm f/6.4 on FF35.
100mm f/4 on APS-C has the same depth of field as 160mm f/6.4 on FF35.
100mm f/4 on APS-C has the same diffraction as 160mm f/6.4 on FF35.
100mm f/4 on APS-C has the same total amount of light as 160mm f/6.4 on FF35.
100mm f/4 on APS-C has the same noise as 160mm f/6.4 on FF35.

If I apply this logic and look at the equivalent of 24-105 f/4 crop equivalence when shot on full frame I get a 15-66 f/2.5. That not very fast on a crop lens is now surpassing the very highly regarded 17-55 f/2.8 in both speed and versatility while also getting better image quality! Also, a great prime like the 35mm f/1.4 L is now an equivalent 56mm f/2.2 lens. Still nice, but not nearly as nice as the real thing and probably equivalent to the much cheaper 50mm 1/4 now.

c) Conclusion

For those of you who are experienced with full frame cameras, especially those of you who have used both formats, are my thoughts above right?

Thanks
Dave