DG 105 can be topped with anything especially with 601 used. No you might not want to 105 915 105 same day but why would you. The fun part for most on this forum is to use different products to see...
DG105/601 great stuff Collinite 915 great stuff have and use both. For protection a lone 105/601 all you need. NOW if you want to change the look 915 might give a little more nuba look. Only if...
I have used Duragloss 501, 105, 111, in the past and just gotten the 601 to try. Will it work better applying 601 in a step alone?? I don't mind the extra work if the out come is better or mix it...