+1 for a couple of the posts above - if you're doing a lot of holes into plastics, and definitely into brass, it's well worth re-grinding the webs, or having 2 sets of every dia you need.
BUT the OP said, and I quote: ..... " I occasionally will drill a hole in metal--anything--say from 1/8" plate to perhaps 1/2" solid bar. Sometimes brass to solid steel. ". To me, the key words in the above quote are "occasionally" and "Sometimes".
Therefore, IME, just about any old HSS drill, coated or uncoated, will do that job/s. Including rolled HSS. Certainly good quality drills will last longer before needing re-sharpening than cheapos USUALLY will. But again, IME, there are quite a few unbranded cheapos about that are every bit as good as (or almost as good as) the name brands. As has been discussed here in a similar thread quite recently, the "trick" is to find out which cheapos are good, and there it seems that only buying and trying will answer that one.
But again, NOT a big deal for someone drilling only "occasionally" IMO. (Aldi/Lidl for example).
So to repeat, I'd never recommend that someone who says he'll only do such jobs seldom/occasionally invests in good quality drill set/s, nor re-grind for the odd brass/plastic drilling job. Used sensibly, just about any old "jobbers" drill with no name brand WILL do those jobs perfectly adequately.