I like Zig 2 in 1 glue the best but do have an ATG.
Yes there are differences in the guns I think different guns take different sizes of tape( the width of the tape roll). I have the yellow gun but am out of tape right now.
But I like the Zig glue because I do alot of small things like gluing eyes on animals or centers on flowers. Plus it works well for making small glitter dots or lines of glitter. Zig comes in different sizes and I usually get the chisel tip for my purposes.