where does everyone take temps on the mamba monster max?(it's mostly plastic)

does anyone have a problem with Fixed emissivity on their laser temp guns it says it doens work on shinny surfaces, is my blue Medusa shinny enough to fall in that category.

also which one do you own and what is your distance to spot ratio d:s if its more than 1:1 do you have to use it at that ratio for best results?

thanks, in other word im looking at getting a temp gun and i think i'm reading into things too much