You will need to be the one to predict your end user and their expectations. If critical, we would recommend that you use a short nap foam or velour roller cover to tightly apply all perimeters against trim or ceiling grids or baseboards. We do allow you to use a foam brush to cut in those edges, but some end users may want you to use the shorter (3”-4”) rollers along those same edges to eliminate any potential for fingering. In most cases, if you cut first and then tightly roll with the supplied foam roller covers along those edges, you should find the result acceptable, but you must address which option is to be pursued with your parties who need to approve the final appearance. It is always recommended to do sample boards before actual application to get the clients approval.