Physical Camouflage VS Improved Invisibility Options

[Levithix]

Is the only advantage (the spell) physical camouflage has over (the spell) improved invisibility the difference in drain?

I was under the impression that camouflage had the advantage against people with low perception checks or for mages who had s decent infiltration dice pool, while invisibility had the advantage against people with high perception checks or for mages who couldn't infiltrate to save their life. But, on reading the illusion spells section on pg. 208 of SR4A it looks like physical camouflage allows the same intuition+counterspelling (if any) test to completely ignore as improved invisibility does.