I don't handle m guys much.... I think they only think of me as their food source... Sure... i'd like to think they like me. But I don't force handle them unless I need to check them out or need to move them (if they wandered off or are upsetting another cham).
I do have chams that handle much more than others. My big melleri Henry looks at me like 'oooh nooo what now' when i pick him up. you can see it in his eyes.. normally he just looks at me and doesn't flinch, but when i am too close he squints his eyes and will spot up. This is true melleri 'i am not comfy' coloration.
Now on the other end of the spectrum I have a panther who could care less about me picking him up. never ever has shown he is unhappy with me other than once I woke him up in the middle of the night. It is only natural he wanted to take my finger off. I also have a veiled who is this friendly. I took him to a SBCK meeting and people there can vouch for how friendly errrr, docile he is.
What I am saying is that it all depends on the cham. If your cham runs away or gapes or lunges, leave them alone. If you see strange color change, it is an expression of mood.
Honestly, chams seem easier to take care of than other lizards, to me, because they can express mood through color. I have a gecko..... and maybe im just not in 'tune' with how they express mood.... but I look at her and no matter what, she seems the same all the time. Maybe I need to spend time on a gecko forum to learn more about leopard geckos.. but she is completely mute to me.