1/2" is too wide for 1/5 scale. Actually, the tapes vary in width depending on where they are. The tapes on the tail surfaces are narrower than the wing tapes, and there are a few of the wing tapes that are wider than others, such as tapes on biased seams. I used 3/8" on my wings and 1/4" on the tail. I made them 5/8" around the wingtips and trailing edges, because they wrap around and the thicker edges of the model don't allow the edges of the tapes to overlap as much.

I think tapes look good, and give a certain amount of dimension, and help break up an otherwise "too smooth" look. If you're doing a Solartex cover, ripping strips of Solartex is a good way to do the tapes, iron them down and do a clearcoat to help seal them and "soften" the edges.Ripping them instead of cutting will give enough of an irregular edge that they will look pinked at that scale.

My favorite pinked tape is the pink (color) hairsetting tape. It is 1/2" wide, adhesive backed and CHEAP, but the pinks are just a tad big for 1/5 scale, but it still looks good and dope will penetrate it. The next best is paper first aid tape, you can get it in 1/2 inch with pinked edges about the same as the hairsetting stuff, or 1" and even 2" with smooth edges. All these are available at your local pharmacy like CVS or Walgreen's. These paper tapes have enough stretch in them that you can easily follow curves, and when you pull them tight along curved edges like wingtips, they will roll over the edges and when you smooth them down there are no wrinkles at all. The paper is very thin, and a couple of topcoats of dope along with light sanding over the tapes, will blend them very well into the surface.