I like to make my own mixes, and stay away from those "looks just like the real thing" stuff, and only buy single-pigment for my basics like Cobalt Blue, Ultramarine Blue, Cereleuun, and the like. When you get a lot of the Thalos, plus white, plus some other color....your mixes can go into weird and creepy places. If I do buy a mixed tube color, I make sure what the ingredients are. For instance, I stay away from Hooker's Green or Sap Green, etc., with Thalo in it...it gives an acidy look (to me) that is quite unnatural, and you have to work at toning it down with even more pigments!
What a hassle, plus you can't get my FAVORITE Olive Green: Old Holland Hooker's Green Light + W/N New Gamboge (to die for, totally transparent)! Try making THAT with a Thalo-based Hooker's!