Say goodbye to tape.
This is not an advertisement, but an endorsement for the best brushes I've ever used for cutting in. No tape is needed because the leading edge is like a blade (no feathering), but the oval base acts as a reservoir to hold paint. The synthetic bristles can be used on all types of paint and are easier to clean than conventional brands. A link is listed below. I like the 1.5-inch for tight detail work and have even been able to do an acceptable job on lap siding. The 2.5 inch works just fine for me on walls and crown molding. I also use the 2 inch for some jobs. The sash edge and short handle make cutting in tight spots a breeze and it saves huge amounts of time. They're made in Wisconsin and sold online at thepaintstore.com. The bristles have a medium texture and may not be stiff enough to paint rough siding, but will cut it in adequately. I'm not a professional painter, but you wouldn't know it with the quality of work I can turn out with these brushes.