Polyester Primers

Ive been painting for awhile,used regular 2k primers and epoxys and since Im starting the bodywork on my Duster,I was thinking about trying out one of the thick polyester primers like Evercoat G2,or Slicksand and wondering if anyone has ever used them?I know it requires a large spray gun needle(about 2.2 )
I may just go with a 2k catalyzed primer,but wanted to know if anyone has used this stuff and if you sprayed it directly to metal with good results.:read2: